Spotlight on Azurite: The Blue-Hued Beauty

Mar 26, 2019

Spotlight on Azurite: The Blue-Hued Beauty

Azurite [Cu3(CO3) 2(OH)2] is a rare copper carbonate mineral formed by either contact between carbon-dioxide-rich water and copper-bearing minerals, or through a reaction involving cupric salts and limestone. Azurite is generally found in massive form (though it occasionally occurs as prismatic crystals), and it is often associated with malachite, chrysocolla, or turquoise, in areas with significant deposits of copper.

azurite malachite crystal mexico pseudomorph pigment Strikingly blue Azurite Crystals with a bit of Malachite. From the Milpillas Mine in Sonora, Mexico.

Azurite is best known for its brilliant, distinctive blue color – which closely resembles that of lapis lazuli. Though its stunning azure blue hue makes gem-quality specimens extremely popular amongst collectors, azurite is not commonly used for adornment. With a Mohs hardness of 3.5 to 4, it is fairly soft, and its tendency to fade from blue to green with exposure to heat and light make it less than ideal for jewelry making.

This softness has, on the other hand, largely contributed to azurite's most well-known historical use – as a brilliant pigment, prized by painters.

Though its original discovered use was in Egypt, as a pigment and dye for textiles, azurite was also commonly used in the east, and its blue tones can still be seen in the cave paintings at Tun Huang in Western China, as well as in wall paintings in Central China which date back to the Ming and Sung Dynasties.

Azurite from GuiChi Copper Mine in Anhui Province, China A shimmering azurite specimen from Anhui, China is an impressive 29cm tall. Joe Budd Photo.

During the Middle Ages and Renaissance period, azurite was prized among European painters. It was used first in tempura and fresco painting, and later in oil. To make azurite pigment, masses of the mineral were collected and ground into powder, which was then washed, and run through a sieve. The grains of ground azurite were separated by size – the heavier, coarse grounds created a dark blue pigment, while the finer grounds were used to create lighter shades.


pseudomorph azurite malachite mineral thumb A Tsumeb Mine Azurite caught exactly halfway in the pseudomorphing process! This is the same process that causes the Azurite pigments to fade to green .

No matter the grain, several coats of azurite pigment were required to create a solid blue color – however, the layering of coat after coat of fine azurite fragments eventually formed a crystalline crust with deep blue hue, and a subtle sparkle. The effect was a rich, beautiful, and brilliant blue, with incredible depth – hence it's popularity.

As mentioned above, Azurite, over long periods of time, can alter to greener hues as a natural change based on the copper in the mineral. This change is referred to as a pseudomorph, and the resulting green color is a related copper mineral by the name of Malachite. This change can be seen in mineral specimens, but it can also be seen in the old paintings that used azurite pigments. One of the most notable works of art affected by this Azurite to Malachite change is Raphael's Madonna and Child Enthroned with Saints. The Virgin was often depicted in a blue mantle but time has turned her clothing dark green. (See the paining here)

First noted as a valuable pigment by Pliny the Elder in the first century A.D., azurite pigment was favored by many masters, including Duccio di Buoninsegna, Johannes Vermeer, Hans Holbein The Younger, and Raphael. Its use continued until the 18th century, when it was replaced by the discovery of Prussian Blue, which was more resistant to the greening and fading which tended to occur with azurite's exposure to the elements.

Azurite is a widespread mineral, and significant deposits have been discovered in France, Greece, Germany, Australia, and Mexico, among other locales. The most prized azurites are crystalline specimens, usually originating in Tsumeb, Namibia, or Morocco. Beautiful crystalline azurite specimens have also been found in the U.S., at copper-rich sites located in both Arizona and Utah.

Arizona Azurite Bisbee Malachite Classic Azurite Specimen from the Famous Bisbee mine in Arizona. Joe Budd Photo.

Azurite's historical connection to artistic endeavors lends additional depth and interest to this stunning blue mineral. Though rarely used as a pigment today, its brilliant color still stands as one of nature's finest, making it a valuable and highly esteemed specimen, which adds distinction to any collection.

To learn more about collecting fine rocks and minerals click here to view our current collection of azurite specimens.



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Tourmaline: Most Colorful in the World?

Mar 19, 2019

Tourmaline: Most Colorful Mineral in the World?

Tourmaline is a very sought-after rare rock amongst fine mineral collectors for its massive range of colors and shades. The depth of color in tourmalines rival that of emeralds, rubies, and sapphires. Yet, tourmaline doesn’t have an extensive history of myths and lore because it is a relatively modern discovery.

Not Quite an Emerald

The earliest known history of tourmaline minerals were as recent as the 16th century, when Spanish conquistadors on the Isla of Elba confused tourmaline for Brazilian emeralds.[1] Tourmaline crystals are highly transparent with a vitreous luster, giving green colored specimens a deep and rich vibrancy that can pass for an emerald. When viewing the tourmaline below (from Minas Gerais, Brazil) it's easy to understand how they might have confused the two.



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Tourmaline remain misidentified until 1703, when Dutch jewelers introduced the mineral to the markets of Europe.[2] Tourmaline would eventually find its way to Tiffany & Company where jewelers discovered a chemical composition that was different from anything else on record.

Later observations would describe tourmaline as a grouping of four different types of minerals – elbaite, schorl, dravite, and liddicoatite – instead of a single mineral. Each type of tourmaline has a similar crystal structure but different chemical compositions that create its unique range of colors.

mint green tourmaline maine crystal for sale Mint green tourmaline from old finds in Newry, Maine

After the discovery of tourmaline as a mineral group, additional mines were found in Sri Lanka, Russia, and the United States. In 1892, gemologist George F. Kunz (the namesake for the mineral Kunzite) wrote a report on the discovery of tourmaline deposits in Maine and California.[3]

Between 1898 and 1914, California was one of the largest producers of tourmaline in the world with crystals coming in rich shades of blue and yellow.[4] The Empress Dowager in China took a particular liking to the pink and red crystals found there, reportedly shipping over as much as her boats could hold. Maine held steadier yields with a greater range in colors and weights, including a blue and green 256-carat stone.[5] Specimens from Newry, Maine have a very distinct color that many collectors can recognize instantly upon sight.

The Phenomenon of Color

elbaite tourmaline crystal mineral brazil pederneira Exceptional 31 cm tall Multi-colored Elbaite Tourmaline from Pederneira Mine, Minas Gerais, Brazil.

The most popular type of tourmaline is elbaite, which offers the widest range of gem-quality colors and gradients. Elbaites are found within granite pegmatites, which are rich in a variety of elements needed to produce the range of colors for which they are famous.

The chemical composition of elbaite contains a mixture of calcium, chromium, fluorine, iron, lithium, manganese, magnesium, sodium, vanadium, and rare traces of copper. The signature “watermelon tourmaline” is formed when there is a change in chemical composition during crystallization, leaving portions of crystal with a red center and green rim. Alternatively (and by similar compositional changes), elbaites can also display bi-color or multicolor changes along the length of the crystal, as perhaps most famously seen in tourmalines from Minas Gerais, Brazil. Multicolor specimens are coveted by gem collectors and specimen collectors alike, as multicolored minerals are rare to come by, especially in the many shades tourmaline can provide.

The liddicoatite type shares nearly mirror-like chemical and aesthetic properties as the elbaite with an equally impressive color range, but with a noticeably larger volume of calcium. Liddicoatite are unique with their trigonal pattern and multi-color zoning that can create some striking formations.

(Love this piece? Learn more on the specimen page.)

Schorl are the most common type of tourmaline, accounting for nearly 95% of tourmaline mined.[6] Most specimens are a solid black color from their rich volumes of iron. Dravite is a marble-like mineral that forms in limestone and is typically a brown-reddish color.

Tourmaline is a beautiful gem-quality stone that comes in a wide-spectrum of colors and shades. Mines in the United States have often supplied much of the world’s tourmaline, and the State of Maine named tourmaline its official state stone in 1971.[7] With multiple colors and a transparent face, they continue to be a favorite rare mineral amongst rockhounds and collectors alike.

Shop our Tourmaline selections to see what treasures we have available!


[1] Various, Tourmaline Gemstones – A Collection of Historical articles on the Origins, Structure and Properties of Tourmaline (Worcestershire: Read Books Limited, 2011), 189.

[2] Sandra K, Gemstone Feng Shui (Woodbury: Llewellyn Publications, 2002).

[3] Donald O. “Tourmaline”. U.S. Geological Survey.

[4] Ibid.

[5] Ibid.

[6] Rod N. “Tourmaline”. HyperPhysics at Georgia State University.

[7] “Tourmaline”. State Symbols USA.

Rare Crystals & Minerals for Corporate Office Design

Oct 3, 2018

Rare Rocks & Minerals for Corporate Office Design

Bringing life into a corporate office is an art that most professionals can appreciate. No one wants to spend over 40 hours per-week in a dull and grey room. Instead, many interior designers use rare rocks and minerals to inspire creative conversations and revitalize a workspace.

Rare rocks and minerals come in various sizes, colors and arrangements that make each piece a unique work of nature. Popular designs that integrate rare rocks and minerals into an office space focus on two main approaches when selecting pieces – centerpieces and accents. To help spark your designer creativity, we’ve organized a list rare rocks and minerals that will brighten any corporate office.

Rare Rocks and Minerals as Centerpieces

When designing an office, the centerpiece is used as the reference point for the rest of the space. Popular minerals that are used as centerpieces include geodes, agates and quartz crystals. These minerals offer a brilliant array of colors, depth and grandiose in their shape.

  • Geodes: After thousands of years in volcanic pressure, the silica within a geode cools and forms a unique display of layered crystals within the geode cavity. The rough exterior of the geode adds to its cavernous aesthetic that makes geodes a great conversational piece.
  • Agates: Formed from the groundwater inside the cavities of igneous rock, agate structures are translucent bands of microcrystalline quartz that come in a gradient of colors and shades. Their multiple layers of color from the chemistry changes found within the water. Their natural designs and colors make them a popular centerpiece for large offices and lobbies.
  • Quartz Crystals: One of the most popular minerals on earth, quartz crystals can from in numerous environments and conditions. Quartz crystals have been found in large sizes and thicknesses, colors and translucencies. Amethyst and Citrine Quartz are some of the most popular crystals for their deep purple and orange colors.
Geodes and crystals in lit cubbies as decor At the Arkenstone Gallery, fine minerals fill custom-built lit cubbies with bright pops of color.

Rare Rocks and Minerals as Accents

Accents are used to give your designed space a finished look. They can range from smaller subtle pieces like bookends to more detailed likes tabletop décor.

The key to using accents in your design is to start with an aesthetic vision in mind. For example, offices that are well lit with white walls may want to introduce light-cool colors to fill the room. Take into consideration how accents will compliment other décor in the office. Some popular crystals and minerals for accents are amethyst, petrified wood, and lapis.

Rare rocks and minerals offer more than a beautiful finish to an office. They bring with them the natural history of the earth, embodying the virtues of patience and consistency to form breathtaking colors and patterns.

See many of the mentioned minerals by visiting The Arkenstone Gallery!

Don’t forget to check our listings for our other shows. The Arkenstone is proud to offer specimens in many displays around the world.


An Evolution of Dr. Lavinsky's The Arkenstone Gallery

May 29, 2018

I was born in 1972. While still a youth, I liked dinosaurs of course (who doesn't?!) and collected fossils in central Ohio by the side of the road - fossils first, crystals later! I went weekly to see the science exhibit of rocks and fossils at COSI in Columbus (a science museum) and marvelled at the natural beauty of these things. I was "found" by an older collector named Carlton Davis collecting fossils by the side of the road in rural central Ohio (Carlton, a well-known collector, was a member of the Columbus Rock and Mineral Society - the wild adventurer, to my mind, who traveled each year to Tucson to buy and compete in exhibition).

After exposure to the club, despite being half the age or less of most folks there, my interest in minerals grew rapidly - a testament to the patience and time spent in those days by mentors in the community and in the local club circuit. There were also books and magazines to read, although they were more scientific and taught little about actually curating collections of these treasures as an asset and for fun - that, I learned by going to small shows and events throughout the Midwest. John Medici, another club member, took me on my first field trip to collect crystals in a quarry at age twelve to Lime City, Ohio (my mom had to go on the museum bus with me as a minor, for liability reasons. She still is mad I lost a boot in the gripping mud of the place...)

To fund my growing hobby, (and that is all I intended it to be!), I essentially became a part-time mineral dealer by age fourteen, selling self-collected Ohio minerals to support my emerging hobby and setting up at the Columbus and Cincinnati mineral shows in their swap areas (where you sold items for "monopoly money" that could be turned in to the real dealers for specimens). I realized that "HEY! As a kid even, I could own stuff as good as in some museums, and handle and hold these things from Nature from millions of years ago?!" and that seemed a crazy revelation.

A young Rob Lavinsky appeared in the  column "Mineral and Fossil Enthusiast", Rocks & Minerals magazine, circa mid-1980s. The photo is taken in his "rock closet" equipped with plastic shelves cut to wedge in.

It propelled me to a fascination with the natural world that led to a Doctorate in science later, but ironically set the stage for a different career in selling these things and building museums as well - I just had no idea, at the time. I also met small town dealers and field collectors, Neal and Chris Pfaff, who were phenomenal field collectors and "the most fair mineral dealers ever," and ended up working for them while I was in junior high school in Ohio. I took the bus up after school, 2 days a week, and helped them and learned from them. I also had a high truancy rate for missing afternoons to leave early and go play with rocks... At that time the Pfaffs specialized in offering tables at shows with specimens that were $10 each or 3 for $25. Selecting and sorting such specimens from their finds taught me a lot about quality and value.

Many days I sat sorting minerals and gluing thumbnail specimens to toothpicks while watching Star Trek reruns. At shows in Ohio, I would run around looking for bargains to trade or buy and then sell “finds” from card tables in the "junior dealers" area of those shows (they used marked monopoly money to make "swap tables" there in the day). I started with $5/10/50 specimens bought with mowing lawns and shoveling snow, combined with spending birthday money on "rocks" instead of video games. My first $500 mineral specimen was in the mid-80s, as I saved up a year's worth of these “swap dollars” to buy a special Indian apophyllite specimen. At first, I tried collecting everything, but he quickly focused on calcites as a species I could collect and really build something around as a "collection" instead of as a "pile of random stuff." I even started exhibiting at local Ohio shows.

A harsh judging when I was 17 or 18 years old at the Berea (Cleveland area) Show admittedly reduced me to tears and convinced me that my talents were not in labeling or organizing an exhibit case at that time! I bought my first $1000 specimen in those days, and my poor mother had a fit about "the rock shop lady" taking advantage of me when I proudly showed her on my return home via the city bus (had no car). View the video below where it's featured in the last few minutes. I still have it to this day and am still friends with that wonderful mentor from the local rock shop. Gloria Olsen is 83 now and just visited me here in Dallas with her affable husband Don.

The mineral hobby transitioned from summer collecting to a business after I went to college (and to my first BIG SHOW - the Tucson Show) in 1991. During my sophomore year at Rice University, I ran out of money and realized that in order to graduate while doing science lab research work in the evenings and weekends as well, I would need to support myself through the hobby instead of getting a "real job." Minerals beckoned! I did shows all over the country each summer, and local street fairs with agate slabs, geodes, and earrings. I also forged links with many sources and dealers, in my travels.

Once, I came across a mineral collector from Milwaukee in a quarry in Indiana, and in getting to know him, found that he had "met a guy who knew a guy" while collecting in a quarry near Atlanta, and turned up a pallet of the old First Issues of Sports Illustrated with a foldout spread of old baseball cards inside. We spent the next 2 years traveling to all the small cities in the eastern USA, doing rock shows and selling those SI issues 2-5 at a time to sports card and baseball card shops along our routes. It paid for a lot of travel expenses!!! Today, they would have been worth a million dollars and more if we had kept them. But at the time, they paid food and gas while we drove around selling and buying mineral specimens.

A funny story about my rise: Sometimes one event stands out. As an undergraduate student at Rice University (a BS in biochemistry and a minor in ancient civilization), I was conveniently located across the street from the Houston Museum of Natural Science. In 1992, the Fabergé exhibit came to Houston, curated by scientists from the Fersman Museum in Moscow, Russia.

Dr. Dmitriy Belakovskiy explores drawers of minerals at the 2017 Dallas Mineral Collecting Symposium

Geologist, explorer, and Moscow native Dr. Dmitriy Belakovskiy (now a close friend!) was sent to accompany the exhibit with a one-way ticket from Moscow and very little money for living expenses and food with his companions. Joel Bartsch, the museum mineral curator at the time who knew me, introduced them to me because he knew I spoke Russian (from high school language class - it was interesting and it was the fifth period, so I could play hookie after that and go work on rocks...). Between my two years of high school Russian and Belakovskiy's rough English, we became friends. In a gesture of kindness to pay their living and food expenses during the exhibit, Bartsch gave these guys two folding card tables to sell minerals (sent over from Russia by colleagues who took them from expedition collections in the basement of the Russian museums!) at the exit from the glamorous Fabergé exhibit---most of them at $1, $2, $5, and $10 each! Between classes, I walked over from Rice University and bought from the tables, wheeling and dealing with the specimens to my own contacts.

As a college student with fast computer access (for that time), I was lucky! Nobody had fast computer connections in 1992, and I lived in a dormitory with free computers and a T1 line. I started some of the first email swap/sell lists before the days of websites. This enabled me to sell to dealers and collectors I had known since childhood in Ohio and from the show circuit. I made my first large deals over $2000 with the Fersman Museum, and I was hooked as a dealer, in hindsight, even if it took a few years to sink into me what was obvious to others. My business grew and grew in my spare time as an undergrad, and I spent a lot of time visiting collections and learning from collectors, who became friends and customers. Those crazy early deals with the Russians really set me on a new road.

Screenshot of in February of 2001 - a rare archival  photo showing the announcement of The Virtual Show, the first online offerings live from Tucson!

INTERNET! Who knew? I had time, I had free computers and access, so one day in 1994 I bought "HTML FOR DUMMIES" at the Campus Bookstore, and tore into it. I put up my first website,, at that time. Nobody could spell it, and people thought I was from Arkansas, so I changed it to shortly after. The internet was wide open at the time. No Google. No Amazon. No eBay. Just a few sites. I put mine up and kept growing it over the years, retooling again and again as the web developed around me, and we found that the mineral market is indeed worldwide, and grew bigger every year once the information and context barriers were broken by the World Wide Web. Business grew. I used to mail VHS tapes around the world with homemade videos of pieces I had for sale. The Internet changed everything.

By design, my website became the largest and one of the first websites with a purposefully broad catalogue of species, quality, and pricing and showing the values of contemporary collector specimens, rather than more common "rock shop" things for the public. I was propelled by the volume I was selling on the Internet to become a “Main Show” dealer at Tucson, our big show - the only major dealer who came up through the web at the time to do so.

At the time I was transitioning to be a dealer in Tucson, I forged an alliance with John Veevaert, a former customer who had become a good friend and fellow website mineral dealer by the late 1990s. Together, we built something we called "The Virtual Show" to convey the energy and excitement, and the new finds, of being onsite at the annual Tucson Show. We sold minerals in gallery and auction formats, and in fact both started our auctions at that time, pushing the frontiers of mineral collecting with the idea and the publicity. Not all folks accepted that the internet was a contribution to the hobby at the time! Few dealers actually understood we were offering specimens in the hallway rooms, to the whole world. Nobody saw the size of the community out there, except us on the statistics reports. TVS ran each year, with specimens and news reports, for perhaps 5 years before we were forced to abandon it due to the workload and went our separate ways. It was a fun adventure I recall fondly now!  We both grew in the process, and John helped me as much as I helped him at the time.

Dr. Lavinsky in the grad lab.... and he hasn't been warned that this photo is being published. Save this photo, fast, before he makes this affable employee remove it!

Despite the lure of dropping out to become a mineral dealer, I loved the science I was involved in and still thought I'd have a career in biotech and academia, so I continued my schooling at UCSD. I earned a Ph.D. in Molecular Genetics ("Genetic Engineering") in 2000 (published in Nature, and then my thesis ended up as a feature paper in Proceedings of the National Academy of Sciences). While writing a doctoral thesis and with a child on the way, I realized the life of a postdoc working in a science lab was suddenly not quite as attractive. I debated whether to go into biotech or work at home as a mineral dealer. With the gracious permission of my wife, I chose the latter - and never looked back.

Since those early Tucson days, I have kept growing my business only as I helped grow the whole trade itself and have been a dealer in the Tucson Gem and Mineral Show™ (TGMS) for over twenty years; promoting the field as a whole and its educational/inspirational opportunities on the website and encouraged both juniors and adults to come into this field. To build on the educational aspect of the hobby, in close partnership with Dr. Gene Meieran, formerly senior Intel Fellow at Intel Corp, I started an annual mineral symposium in Dallas that now attracts hundreds of collectors for a mineral immersion weekend. I also signed on to help produce a PBS television reality show, Mineral Explorers.

Another of my projects was to be a sponsor of The World’s Most Precious Treasures, a reality television documentary following gem tanzanite from the mine to the market in Tucson; it was made by French National Television in association with the gem company Cartier of Paris and has aired in Europe now.


In addition, I organized and planned the Chinese Crystalline Treasures exhibition at the University of Arizona in 2013 in conjunction with partners at the university. The book on the exhibit (online: is really a short introduction and primer to collecting fine minerals in general; and later it was published in Chinese by the Hunan Provincial Government (the first officially authorized and translated U.S. mineral magazine issue of any kind in China). It's also available as a free interactive e-book.

This is the template for a future museum exhibition, hopefully coming soon to Dallas and then Los Angeles or another city in 2021 or 2022! I have been lucky to be accepted by the community of museums in China and have taken the educational mission in China very seriously, traveling there often for talks and experiences, as well as buying trips.. It has truly been an adventure, and not one that I knew I would have when I started "collecting rocks" as a kid!

After maintaining several different gallery locations, I'm excited to have our new gallery in Dallas, opened in early 2018, to showcase these natural treasures for what they are: Art.

Minerals and gems expo set to sparkle in Chenzhou

May 17, 2018

Latest event will showcase Hunan province city's expanding business opportunities and draw international interest with exciting exhibits and displays

By Zhao Shijun
Originally published on

Stage at the Chenzhou China Mineral and Gem Auction A fantastic stage set the mood for the Fine Mineral Auction at the China Mineral and Gem Expo in Chenzhou, Hunan, China. Monica Kitt Photo.

The China (Hunan) International Minerals and Gem Expo - staged each year in the city of Chenzhou, Hunan province - is set to again draw international interest and showcase the city's bright business opportunities, according to local officials.

This year's expo, the sixth show, will open on Friday and organizers said it will be another dazzling extravaganza.

They said a total of 2,800 exhibition stands, covering about 120,000 square meters, have been booked by more than 1,000 exhibitors from over 50 countries and regions including France, the United Kingdom, Italy, Germany, Belgium and Brazil.

Liu Zhiren, mayor of the mineral resource-rich city, said he believes the expo will continue to play its role as a platform to publicize the city's business environment and forge deals, helping attract overseas businesses and push local companies into international markets.

Read the full story here


10 Facts You Didn’t Know About Gold, Part 1

Feb 27, 2018

Most people understand gold in terms of wealth and investments, but there is so much more to say about the mineral. Gold has had a long history as a currency and as a sign of power. Today, gold’s unique qualities have expanded its role as a conductive material, decorative accent, and a mineral collector’s favorite. Here is part 1 of our 10 facts about gold that you didn’t know:

Gold can be found around the globe

Gold can be found on every continent, including discoveries in Antarctica. However, not all locations hold equal amounts of gold. For centuries, the two largest deposits of gold were found in South Africa and India. Australia's gold rushes began in the mid-1800s. When South African gold began to peak in the 1970s, other locations like Russia and the North American continent began to boom as the leading producers of gold. Brazil recently has hit a small deposit of beautiful crystallized golds.

Several gold crystals from Brazil Brazil recently had a find of beautiful gold crystals.


We’ve produced enough gold to fill two Olympic swimming pools

Two Olympic pools or 5 million liters is a figure that is frequently cited by publications using Thomson Reuters GFMS survey.[1] The truth of the matter is that coming up with an exact number is incredibly complicated, as many countries are secretive about the amount of gold they hold.

Mining for gold has been a practice for growing wealth since before the ancient Egyptians. History holds countless legends of gold hordes like Francisco Pizarro’s treasure exploits filling a 22-ft. by 17-ft. room and hundreds of bullion chests aboard sunken ships like the Nuestra Señora. Still “Two Olympic pools” is a safe estimate with cross surveys by the U.S. Geological Survey and the British Geological Survey.[2]

There is more steel produced in an hour than gold in its entire history

Gold is incredibly rare. In fact, the world produces more steel in an hour than it has ever produced gold since the start of written history. Looking at the number, the world increases the production of steel by 10,500 tons per-hour while gold production increases by 2,000 tons per-year![3]

Platinum from Siberia, Russia. Crystallized platinum, an example of a noble metal is exceptionally rare.

Gold is a “noble metal”

“Noble metals” are a rare group of metals that resist corrosion and oxidation from moisture in the air. This is because gold’s electronic configuration prevents its electrons from reacting with chemicals that would cause base metals to rust or tarnish.[4] Other metals included in the “noble metals” group are silver, platinum, rhodium, and palladium.

Earthquakes can create gold

A recent study by the University of Queensland in Australia discovered that water in faults vaporize and make gold during an earthquake.[5] During an earthquake, water moves from bigger faults to smaller fractures throughout the earth. At around 6 miles below the surface, the intense heat and pressure carries concentrated carbon dioxide, silica, and gold. When the pressure drops, the water is instantly vaporized to forcing out silica and gold.


Gold specimen from California on a custom lucite base Stunning gold from the Eagle's Nest Mine (Mystery Wind Mine) in Mariposa, California

Our fascination with gold has found many incredible facts about its history, uses, and qualities. Be sure to join our mailing list to stay updated.

Looking for gold pieces to add to your growing rare rock and mineral collection? Then follow the Arkenstone on their many mineral shows throughout the year! Information on the shows we’ll be attending can be found on our Mineral Shows page. We’d love to meet with you and talk about the specimens in our collections!

We’ve recently updated our galleries with specimens from around the world. You can find our latest collections here.

[1] Ed P. “How much gold is there in the world?”. BBC.

[2] Ibid.

[3] Vronsky. “History of Gold”. Gold-Eagle.

[4] Bjørk H. “Why gold is the noblest of all the metals”. Nature.

[5] Deon W. and Richard H. “Australian research confirms link between seismic activity and gold deposits”. The University of Queensland.

Visit a Gallery, a Museum and the Dallas Symposium: A Hands-on Education

Feb 22, 2018

There’s no greater fulfillment in collecting rare rocks and minerals than seeing an incredible specimen in person. Not only is it a rare opportunity to engage with scholars, you’re also bound to learn a wealth of information that cannot be found in an article. This is why we at the Arkenstone encourage enthusiasts to visit museums and symposiums to see rare minerals that couldn’t be found anywhere else.

The founder of the Arkenstone, Dr. Robert Lavinsky, has woven this passion for hands on education into the culture of the company with several specimens in display at the Smithsonian Institute, Harvard University, the California Institute of Technology, and many others. In our opinion, here are some reasons to start planning your next museum or symposium visit today:

You’ll See Premier Specimens

Going to a museum or symposium gives you the chance to see some of the finest specimens found on earth and learn from experts. It’s one thing to read about a rare rock in a magazine or online article. Being up close and personal with some of the earth’s rarest minerals like benitoite, red beryl, euclase, and alexandrite is a far richer experience.

You’ll See Complete Collections

Fine Sapphire Crystal, Sri Lanka. Natural sapphires like this one are judged on criteria like crystal shape, color, and the rarity of the location. Joe Budd Photo.

The most exciting part of visiting a museum or symposium are its complete collections. Some minerals like sapphires come in a variety of colors with large specimens being incredibly rare. Visiting an exhibit with an entire collection is a unique opportunity to indulge in a collection that would otherwise take dedicated years and resources to complete.

Some museums dedicate entire rooms to collections by world famous hobbyists and researchers like the Smithsonian Natural History Museum’s Janet Annenberg Hooker Hall. The museum is residence to over 2,500 minerals and gems, including the Hope Diamond and the Star of Asia sapphire.[1]

The Hope Diamond is one of the most recognizable gems in the world. The Hope Diamond at the Smithsonian, one of the world's most famous gems. By David Bjorgen - Own work, CC BY-SA 3.0

You’ll Meet Experts in The Field

There’s no shortage of rare rock and mineral experts when you visit a museum or symposium. Museum curators and docents have extensive background knowledge about the rare rocks in display and will happily offer references for further studies.

Symposium events like the annual Dallas Mineral Collecting Symposium and the Tucson Mineral Shows bring hundreds of scholars and enthusiasts to review the season’s most important discoveries and research. These events typically have showrooms available, allowing you to network with other enthusiasts.

Opportunities to Handle Rare Minerals

Sulfur from Sicily, Italy. Photo by Joe Budd, courtesy of The Arkenstone, Sulfur from Sicily, Italy. Photo by Joe Budd.

A great way to familiarize yourself with the spectrum of rare rocks and minerals is to observe their physical properties. From the surprising smell of sulfur to the unexpected weight of gold, handling rare minerals provides deeper insight.

Some museums have special exhibits planned that allow visitors to handle specimens. The National History Museum in Los Angeles County encourages visitors to handle their slabs of jadeite – a highly praised material around the world.[2]

Visiting a museum or symposium offers unique opportunities that can’t be experienced anywhere else. So, fit a trip into your next vacation or outing today!

Looking to start your own rare rock and mineral collection? Follow the Arkenstone on their many mineral shows throughout the year! Information on the shows we’ll be attending can be found on our Mineral Shows page. We’d love to meet with you and talk about the specimens in our collections!

We’ve recently updated our galleries with many impressive specimens from around the world. You can find our latest collections here.


[1] “Museum Event Spaces”. Smithsonian Natural Museum of Natural History.

[2] “Gem and Mineral Hall”. Natural History Museum.

The Vibrant Glow of Electric Hyalite Opals

Feb 18, 2018

Opals are some of the most unique gems found on earth for their wide display of color. Fire opals are revered for their translucent coloring with flashes of red and yellow hues. Lightning ridge opals are a darker variety with splashes of red and green.

Of the many opal varieties, one of the most unique versions is hyalite opal. But unlike the fire and lightning ridge opal,  hyalite opal’s display of magnificence is best seen in the dark... check out what happens in the video below when the lights go out and a blacklight comes on!

The Opal with a Fluorescent Glow

One of the most captivating qualities of hyalite opal is its fluorescent green glow in shortwave ultraviolet light. All minerals can reflect a degree of light, but some have the physical qualities that allow them to temporarily absorb a small amount of light and releases it in a different wavelength.

While the hyalite opal may appear milky to colorless, with certain "electric" hyalites, the change in wavelength is visible to the human eye as a glow that is intensified just by sunlight or moving into a dark room.

Hyalite Opal, like this specimen from Hungary, shows shocking fluorescence under UV lighting!

How the “Bubbles” Are Formed

At a glance, hyalite opal looks like a cluster of milky bubbles on sedimentary rock. This globular mass comes in irregular shapes and sizes, giving it a weak opalescence (play of color) that is a hallmark of other precious opals. The tiny beads of hyalite contain around 3-8% water and are made of hydrated silicate.[1]

Like other opals, the hyalite opal lacks the crystal structure of most minerals. Instead, they form spherules through the layered massing of silica gel.[2] To form hyalite opals, the layered massing of silica must solidify within its gas phase. Most of this activity takes place within irregular crusts of volcanic and pegmatite environments.

When the exposed lava begins to cool and harden, gasses rich in silica and water travel through the cooling lava and the bodies of rock around it. Some of the silica and water rich gas is trapped in fissures and pockets within the rock, continually cooling and lowering in pressure as it turns into a liquid. The byproduct of this process is a bubbled botryoidal crust of hyalite opal that is less hydrated than precious opal.

This pale yellow opal from Mexico glows neon green under blacklight. Gemmy field of lustrous, green, botryoidal Hyalite Opal that has bright fluorescence. From Zacatecas, parts of this Opal are a full half centimeter thick with plenty of cutting material. These fluoresce in the natural sunlight, just holding it outside!

Hyalite opals can be found in precious opal-rich regions around the world like Australia. The most common regions that produce the most hyalite are Central Europe, Northeastern United States, and Mexico. Recently, major discoveries of hyalite opal have been in the Zemplen Mountains of Hungary and Zacatecas, Mexico.

Opals are revered for their wild display of color. While the hyalite may not have the impressive color splashes of the lightning ridge or the striking yellow of a fire opal, their fluorescent glow is vibrant and must be seen to believe it!


Interested in adding a hyalite opal to your collection? Browse specimens for sale from Mexico and Hungary.


Follow the Arkenstone on their many mineral shows throughout the year! Information on the shows we’ll be attending can be found on our Mineral Shows page. We’d love to meet with you and talk about the specimens in our collections!

We’ve recently updated our galleries with many impressive specimens from around the world. You can find our latest collections here.

[1] “Hyalite”. Mindat.

[2] Franca C, et al. “Physical and chemical properties of some Italian opals”. Periodico di Mineralogia.

5 Incredible Minerals Sold in an Auction

Feb 6, 2018

One of the best places to find high quality rare minerals is in an auction. Dealers bring their finest specimens forward for collectors to appraise and cast their bid to take home the prize. Now, with the internet connecting communities from around the world, online auctions like are making it easier than ever to bid for incredible rare minerals – bringing more diversity and excitement to the mineral world!

Mineral auctions are growing and sometimes we see news breaking sales of one of a kind minerals and purchases. To celebrate the spirit of mineral auctions and the sought-after minerals ever found, here’s a list of 5 incredible minerals sold in an auction:

The Rockefeller Emerald

The Rockefeller name is woven in the fabric of American history with the Standard Oil Co. Inc. of the 1900s and many other entrepreneurial achievements. Adding to the Rockefeller legacy is the most expensive emerald in an auction, at $305,00 per carat: The Rockefeller Emerald.[1]

The 18.04-carat Rockefeller Emerald was purchased by Harry Winston for $5.5 million at the Christie’s Auction house in New York, New York. The Rockefeller Emerald was first acquired by John D. Rockefeller Jr. in 1930 as a center stone for a brooch. In the 1940s, the emerald was placed into a platinum ring. Images and more details available here.

The Sunrise Ruby

Original work: Société Cartier; Depiction: Justin Tallis Sunrise Ruby - one of the most valuable gemstones sold at auction - weighs in at 25.59 ct. Cartier Photo.

Rubies are one of the rarest minerals in the world with valuable qualities that are increasingly hard to find in nature. As a red variety of corundum, rubies have an intense red color that come from their chromium impurity, separating them from their sapphire cousins. Large carats of rubies are exceptionally rare, so it should be to no surprise that a 25.59-carat ruby called, “The Sunrise Ruby” sold for a record of $30.33 million at Sotheby’s in Geneva.

Praised as “amongst the rarest of all gemstones” by David Bennet, head of Sotheby’s international jewelry division, The Sunrise Ruby is one of the few rubies in the world to have the rare grading of pigeon’s blood color at its size.[2]

Blue Moon of Josephine

Described as “flawless” by the gemstone world, the 12.03-carat Blue Moon of Josephine was auctioned for $48.5 million at Sotheby’s in Geneva.[3] The diamond was bought by Joseph Lau, a billion from Hong Kong, as a gift for his daughter. The Blue Moon of Josephine is an exceptionally rare blue diamond with a hue described as Fancy Vivid by the GIA. Fancy Vivid describes a gemstone whose medium to dark tones are strongly saturated and have only been found in 1% of all blue diamonds.[4] Photos here.

Oppenheimer Blue Diamond

While the Blue Moon of Josephine broke records for being one of most expensive blue diamonds per-carat ever auctioned, at $4 million per-carat, the record for most expensive blue diamond ever auctioned goes to the Oppenheimer Blue. The 14.6-carat blue diamond was auctioned at Christie’s in Geneva for $57.5 million, making it the largest Vivid Blue diamond sold at an auction.[5]

The Oppenheimer Blue diamond was named after Philip Oppenheimer of the De Beers Diamond Jewelers. Blue diamonds are an exceptionally rare type of diamond with only 10% of all found blue diamonds being larger than a carat.[6] The Oppenheimer Blue is truly a one-of-a-kind gem with qualities that place amongst the rarest of the rare. View the amazing photos here!

Pink Star Diamond

Earlier this year, the attendees of Sotheby’s in Hong Kong witnessed history as the world record for the most expensive gemstone ever sold at auction took place. The 59.6-carat Pink Star Diamond, a diamond recognized as the largest Internally Flawless Fancy Vivid Pink by the Gemological Institute of America (GIA), sold for $71.2 million.[7]

According to Sotheby’s, The Pink Star Diamond was mined by De Beers in Africa in 1991 and was 132.5-carats. The rough diamond was then “meticulously cut and polished over a period of two years.” View the results!


Want to stay up-to-date on the latest news and events about the mineral world? Register for the Arkenstone’s mailing list for information on the latest findings, news, and many mineral show announcements throughout the year!

We’ve recently updated our galleries with many impressive specimens from around the world. You can find our latest collections here.

[1] Roberta N. “Harry Winston Pays $5.5 Million For Rockefeller Emerald: Most Expensive Per-Carat Emerald Ever Sold”. Forbes.

[2] “This ‘pidgeon blood’ ruby sold for a record $30 million’. Business Insider.

[3] “Tycoon buys $48m blue diamond at auction for daughter”. BBC.

[4] “World Auction Record Price-Per-Carat for a Diamond or Gemstone”. Sotheby’s.

[5] “The Oppenheimer Blue”. Christie’s.

[6] Cecilia J. “’Oppenheimer Blue’ diamond sets new record, fetches $57 million”. Mining.

[7] Merrit K. “’Pink Star’ Diamond Sells for $71 Million, Smashing Auction Record”. NPR.

The Rarity of Tanzanite

Jan 17, 2018

By Robert Gessner BSc GG, Gessner Gems
Reprinted with express permission from the author

In 1967, blue-violet crystals of the mine- species, zoisite, were discovered south of Mount Kilimanjaro in northeast Tanzania. The host rocks of the discovery, which are orders of magnitude older than Africa’s highest mountain, form part of the Lelatema Mountains which are located very near the town of Merelani. In 1968, Henry Platt of Tiffany & Co. christened the new and remarkably beautiful zoisite gem,Tanzanite, to honor its single-source discovery in Tanzania. The 50th anniversary of its discovery is marked in 2017 and is the most notable and exciting event of the gemstone industry of the 20th Century.

Bright blue tanzanite crystals are rarely found in sharp crystals like this. Orthorhombic crystal termination seen on the blue axis of a Tanzanite crystal. Robert Gessner Photo.

What makes this gemstone even more interesting and unique, and sets this beautiful stone apart from all others, is its remarkable rarity. Crucial in understanding its rarity is that this stone is the only one (or, one of the few) that evolved from a collector’s stone, only available to a few, to a commercially available stone. But this is only for a limited time: our generation. Tanzanite is found and mined in only one place on earth: a 7 square km area that outcrops near the town of Merelani in northeast Tanzania.

View of Mount Kilimanjaro from Block C overlooking Block D. Robert Gessner Photo

It is found in only one place on earth because of a very complex and unique set of geological conditions that came together during the breakup of the supercontinent, Gondwana, between 1.5 and 2.5 billion years ago. My intention is to not get too technical, but the geological origins are so interesting, and for me, the start of the story that I want to share, creating excitement for current and future owners and highlighting the fact that this gemstone is only available for a single generation: our generation.

The most striking feature of Tanzanite is its color. Or colors. It is a pleochroic gemstone. More specifically, a trichroic gemstone simply means that it naturally displays a different color in each direction, or on each axis.The fine crystals display intense, well-saturated and deep colors. The color-causing element (or chromophore) of Tanzanite is vanadium. Think of it the same as the element chromium giving Rubies their red color. The vanadium is responsible for the blue-violet color in Tanzanite. If any geological history needs to be mentioned, it is this because the rare availability of the vanadium during Tanzanite’s formation is what ultimately is responsible for what makes this gemstone so beautiful, desirable, and popular.

Tanzanite crystal in a pocket in Bravo Shaft. Robert Gessner Photo.

The vanadium is a trace element that came from the organic (tree and plant) material that was deposited with eroded silica-rich sands and calcium-rich (shell and ocean-life) material in a deltaic/shallow sea environment over millions of years during the gradual break up of Gondwana.This accumulation of layers was subsequently buried and metamorphosed at high temperatures and pressures.The organic material became graphite, the silica-rich sands became the schist and gneiss, and the calcium-rich material became dolomite (an impure marble). All these rocks are seen in the deposit.

At 500 million years, a geological event resulted in the crystallization of Tanzanite. Erosion on the surface on the earth and the natural upliftment of continental crust (in respect to the denser and heavier oceanic crust) brought this deposit to the earth’s surface where Tanzanite was found for the first time in 1967.

Pocket containing Tanzanite in Bravo Shaft. Robert Gessner Photo

The transition from a collector’s stone to being commercially available started in earnest in the late 1990s when the Tanzanian government started adequately regulating the deposit by subdividing the 7-kilometer section into Blocks A, B, C, D, and D-Extension, respectively, and granting mining licenses to companies and individuals at different levels of investment ability. Block C, the largest 2 km 2 of the 7 km 2 , was awarded to African Gem Resources Limited (Afgem), a private South African company, after winning the tender in 1998. Only in the early 2000s did the company start investing heavily in geology and mining as production was decreasing and becoming more haphazard after an initial and significant bulk sample that raised millions of dollars for Afgem.

The investment in geology and mining resulted in a better understanding of the deposit’s geology and the Tanzanite-bearing structures, and in turn increased the company’s production. The increased production resulted in increased revenues that were put back into the mining. More shafts were sunk, more mining faces were created, and from a geo - logical point of view, more geology was exposed on the sidewalls. With all this work, a geological model was created, as well as an understanding that was never in place before. Another result was production areas could now be proactively planned as opposed to a history of reactive mining. Essentially, we were able to get the mining into the right places. As a result, from 2005–6, production from the company improved to more consistent commercial volumes. It must be noted that at no point can a geologist predict the gemstone; we are always predicting the geology in which the gems are formed. From mid-2000, the consistent production from the mine was a result of having the mining faces in the right areas. If one face was not producing, another one was.

In late 2004, Afgem become a publically traded company, TanzaniteOne Mining Limited (TanzaniteOne), and listed on the London Alternative Market (AIM).

Self-portrait taken August 2005 from the largest pocket of Tanzanite I have seen in the deposit! Robert Gessner Photo.

Large-scale mining operations generate not only more production volume, but also more volumes of all grades, more consistently. As a result, a master grading set was created. For the first time, rough Tanzanite could be parceled for size, colour and quality to its sightholders. By definition, this system of product presentation for rough sales could only work with regular and good volumes of production from the mine. This was a direct result of the size of the deposit being professionally mined, with regular production and future exploration.

Afgem initially, but then TanzaniteOne, took a collector’s gemstone to one that became commercially available around the world. But the story does not end there. Because it is commercially available does not mean that Tanzanite is any less rare than it originally was. It just became accessible to everyone; but only for a limited time: our lifetime. Found for the first time in 1967, it can be estimated that the gemstone will no longer be accessible, particularly commercially, within a single generation of its discovery. The most common understanding of this is that the deposit gets physically exhausted (mined out), but the actual concept is that the costs to mine become too high versus the income from sales (i.e., the gemstones are still in the ground but are physically too deep to mine–too expensive). This factor highlights its generational rarity, which the current market and value of Tanzanite do not indicate. The market and consumers think that because there are high volumes of Tanzanite available at the moment this will continue; but this not the case.

The current prices of Tanzanite, particularly at the wholesale level, are actually too low; too low for how rare the gemstone is, and too low for future mining. The amount of Tanzanite on the market currently should be seen as a bubble and temporary; it will not continue. There has been a lot of recent supply due to many miners being in the right areas and producing, with this product subsequently making it to the wholesale market. This is the reason for the low wholesale prices, but with the mines getting deeper, and the natural pocket effect of Tanzanite, this will not continue. The reality is that the deeper the mines get, the more expensive it will be to mine. For future years of supply, the wholesale prices need to increase.

Tanzanite crystal in Main Shaft. Robert Gessner Photo.

Single generation is a phase coupled with Tanzanite since its marketing in the 2000s, and this itself, evokes its own romance, beauty and rarity. Trying to tie the availability to a number of years should not be the discussion point, and according to me, less importance and significance should be given to it. The history of the talk of only available for another 10 years, or 15 years ties in to large-scale public mining at companies attempting to quantify its resource for value purposes and investment, which the previous owners in the 2000s took to the market to create desire and indicate its rarity. There are too many factors that affect a number like this, so it should only be seen as guide and less importance should be given to it. No one asks how many years are left of the Colombian emerald deposit, or the Burmese Ruby deposit. It cannot be defined, so why should the Tanzania Tanzanite deposit be defined? The famous Brazilian Paraiba Tourmaline and Russian Demantoid Garnet deposits are now mined out, and very little or no material is available anymore; nothing significant in recent years anyway. Old stock or old mined material that do become available command extremely high prices today. We can only look back and say that we should have bought then. This will be the same for Tanzanite. Buy now, as the prices are low–for the moment. All gemologists know that Tanzanite is trichroic. It is also part of the orthorhombic crystal system. As Tanzanite extracted from the earth is often in its perfect rectangular crystal shape, it is easy to see its trichroism (meaning you can see a color on each axis, or side of the gemstone). These natural rough crystals can show either a 3-colour trichoism combination of blue, violet, and brown (combination of red/yellow/green) or a 3-colour trichroism combination of blue, violet, and violet (so two violet axes, or sides), respectively. The reason for the two combinations of trichroism is due to natural (in the ground) heating that a percentage of the natural crystals were locally subjected to. The natural heating has removed the original red/yellow/green on the “brown” axis to colorless, and so the (second) violet color is seen. Technically, this has been achieved by an intervalance charge transfer during heating of Ti3 + to Ti4 +, which is colorless. [As all chemical equations require balance, the second change is a slightly stronger blue-violet (so the V4 + to V3 +). The colour change due to heating is a stable change. As this heating takes place naturally, it is impossible to distinguish between post-extraction (or by man). The result of this means that there are only two realities to label a tanzanite gemstone: no heat or no heat treatment by man. The first is that the gemstone in question displays its blue, violet, and brown trichroism, and the second condition is that a strict and traceable provenance of no heating by man exists of a blue, violet, and violet trichroism gemstone directly from the earth, through the trade to the wholesaler/retailer.

Trichroic pleochroism of Tanzanite under incandescent light. Robert Gessner Photo.

This second condition may be a potential option but is strictly tied to a person’s honesty, because it is scientifically impossible to prove. Another wonderful and valuable characteristic of Tanzanite is that there is only natural Tanzanite in existence. Man cannot create Tanzanite due to its unique formation in the earth and its chemistry. Imitations, by definition any material that looks like a natural gem and is used in its place, do exist but any trained gemologist would be able to confirm whether it’s natural or not with a few simple gemological tests. Tanzanite is a rare gemstone with both a remarkably unique geological history and a success story in the jewelry market and in our homes; a story of rarity that needs to be shared; a story that is hidden within each piece of Tanzanite worn by its owners.

By Robert Gessner BSc GG,Gessner Gems

Article as published in AGTA Prism, Volume 4, 2017, viewable online here.

Article adapted from its original as it appeared in the GemGuide, Gem Market News, November/December, Volume 36, Issue 6 published by Gemworld International.


About the Author: I am geologist by profession having completed my BSc Degree in Geology at the University of Cape Town (UCT), South Africa, in 2002, and completed my post-graduate Honors Degree at the University of Stellenbosch, South Africa, in 2004. My first colored gemstone industry opportunity was in Tanzania in 2003, which has become my specialization and career. I have over 13 years of colored gemstone geology and mining experience in East Africa working specifically with Tanzanite, Tsavorite, Zambian Emerald. In 2016, I graduated as a Graduate Gemologist (GG) from the GIA in Carlsbad, USA. Today, I am based in Los Angeles, and have my own business offering consulting, training and gemstone sourcing.