Rock Roundup: April 2023 Edition

May 1, 2023

Welcome to the monthly rock roundup, where we recap some of our favorite and interesting specimens that we’ve released for sale this past month. In case you missed it, he’s a quick rundown on some of what we think you should check out. This edition we’d like to focus on some significant updates from the Bill and Anne Cook Collection, Mango Quartz, and Peru updates!

New Updates from the Bill and Anne Cook Collection

Bill and Anne Cook were known for collecting a wide range of crystals. From their suite of exceptional thumbnails to remarkable mixed minerals in miniature through cabinet size range, we are excited to offer fine minerals from their collection starting in the hundreds of dollars, reaching into the 5-figures! You can view specimens from the Bill and Anne Cook Collection that are currently available on the website here.

Here is a little background on Bill and Anne Cook as presented by under the page for Wilancookite, a mineral named after them by Luis Menezes.

Named after William (“Bill”) (1927-2006) and Anne (1928-2021) Cook, an avid mineral collector couple. Bill had a PhD in geology, and was a crystallographer at Clevite Research, which became part of Gould. When that company closed its research center in Cleveland, he with several others founded Cleveland Crystals, Inc., which became a pre-eminent grower of electro-optic and nonlinear crystals. He also served for many years as adjunct curator of mineralogy at the Cleveland Museum of Natural History. Anne, a mathematician, worked in the engineering department of AT&T and later as a math tutor at two high schools in the Cleveland area. She served as president of the Midwest Federation of Mineralogical Societies, and for many years as secretary of the American Federation of Mineralogical Societies. The Baltimore Mineral Society inducted Anne Cook into the Micromounters’ Hall of Fame at the 63rd Annual Paul Desautels Micromount Symposium in Baltimore on October 12, 2019. Both Bill and Anne, at various times, served as president both of the Mineralogical Society of Cleveland and of the Micromineral Society of the Cleveland Museum of Natural History.

– Excerpt from the “About” section of Wilancookite on

You can also view a photo of Bill and Anne here on as well (photo by Jeffrey Shallit).

Very Rare Native Mercury from Socrates Mine, California, USA

Extremely rich specimen liberally covered with silvery droplets of Native Mercury. Mercury is the only recognized mineral that is found as a liquid at room temperature and is quite rare in specimen form. The specimen has been sprayed with clear lacquer to stabilize the mercury – which is a standard procedure for Mercury to stabilize the droplets. NOTE: This specimen should only be arranged for pick up at a major show, or at our gallery for hand delivery. Learn more about this Native Mercury specimen here.

Mercury and Cinnabar from Socrates Mine, Sonoma Co., California, USA

Classic, Bright Chrysocolla ps. Azurite from, Ray Mine, Arizona, USA

An aesthetic, classic pseudomorph of Chrysocolla after Azurite from the Ray Mine of Arizona, probably originated from the 2280 Level. These old classics are rarely seen for sale. Superb for its size with unusually elegant structure, beautiful color zoning from light blue-green to darker teal, and well terminated across the main, vertical crystals. Learn more about this Chrysocolla after Azurite specimen here.

Neon blue chrysocolla after azurite thumbnail from Ray Mine, Pinal Co., Arizona, USA.
Chrysocolla ps. Azurite from Ray Mine, Pinal Co., Arizona, USA

Exceptional, Gemmy Orpiment with Calcite from Jiepaiyu Mine, Hunan, China

The exceptional orpiment specimens from the Jiepaiyu Mine in China (1990s) were long considered the best in the world and easily rival the best of those from Peru or Nevada, with their divergent clusters of bright orange, prismatic crystals like you see on this piece. This is a killer specimen with magnificent color on over two dozen, gemmy, lightly striated, lustrous and huge orpiment crystals; one of the better examples in this size from 1990s era production. Learn more about this orpiment specimen here.

Orpiment with Calcite from Jiepaiyu Mine, Shimen Co., Changde, Hunan, China

Pristine, Glassy Lazulite with Siderite from Rapid Creek, Yukon, Canada

This significant cluster of lustrous, indigo-blue crystals of Lazulite with large crystals was probably from the 1970s or early 1980s finds in the Yukon Territory. The display area features at least two dozen fairly isolated, sparkling, glassy, and unusually pristine Lazurite crystals interspersed with brown Siderite in a shallow, concave, elongate vug of host ironstone rock. From Canadian collector Claude Begin, to the Cooks. Learn more about this Lazulite specimen here.

Lazulite with Siderite from Rapid Creek, Dawson Mining Dist., Yukon, Canada

Magnificent, Cherry-Red Realgar on Calcite from Jiepaiyu Mine, Hunan, China

An eye-catching, sharp, lustrous, gemmy, cherry-red, prismatic, perfectly formed Realgar crystal sits isolated on a large crystal portion of off-white Calcite with dove-gray highlights around the edges. The contrast between the two and the superbly isolated Realgar makes for an ideal, well-composed specimen! This specimen was something Rob purchased for his personal collection from the sale of the F. John Barlow collection in 1999 and later sold to Bill and Anne Cook between 2001-2003. Note: Realgar should be stored out of light (such as in a closed opaque box) to preserve this gemmy, cherry red color. Learn more about this Realgar specimen here.

Realgar on Calcite from Jiepaiyu Mine, Shimen Co., Changde, Hunan, China

Beautiful, Hand-Picked Mango Quartz

In addition to the wonderful offerings from the Bill and Anne Cook Collections, we’ve also added a few other noteworthy updates this month! We are pleased to offer our first ever release of “Mango Quartz” featuring a fine selection of cherrypicked specimens from a direct source in Tucson 2023 of this fine material from Colombia! Mango Quartz (Quartz incl. by Halloysite) first hit the market in 2018. We have not yet offered it in part to evaluate context and value as more continue to come to market. We had an opportunity to meet a source at Tucson this year, and hand-select pieces from a group of over 2000 kg of specimens from December and January pockets that arrived to Tucson during the show. View the Mango Quartz Gallery available on

Stunning Peruvian Treasures

As seen in our recent Wisdom Pocket blog updates, we also posted a fine selection of minerals and crystals from Peru, including rich green Fluorites, bright metallic Pyrites, deep red Rhodochrosite, intense blue Chrysocolla, and more. Read up on some of our favorites on our recent Peruvian Treasures blog, view this specimen below here, or view all available specimens from Peru here.

Mirror-like pyrite with sphalerite from Peru.
Pyrite with Sphalerite from Huanzala Mine, Huallanca Dist., Bolognesi Prov., Áncash, Peru

Looking for other specimens? Head to to explore some of the available offerings we have, or send us an email at for assistance with custom sourcing a specimen for your mineral and crystal collection.