ex. Marilyn Dodge
An excellent Bournonite specimen, having excellent form and superb luster. For the locality, this is exceptional! It is complete on all sides as you can see, and very fine!
Thumbnail, 2.5 x 2.5 x 2 cm A brilliantly lustrous cluster of truly fine bourno crystals perched on a mound of galena. Nice!
A rather unusual large plate of bournonite crystals, all showing sharp UNTWINNED crystals to 2.25 cm in size. This is actually more uncommon, compared to the twinne dform of the mineral. The crystals form this locality are sharp and gun-metal lustrous, making for very dramatic bournonites. The matrix contrasts a bit more in person than it appears, and is coated with sparkly druse of other sulfides such as pyrite. This is a rich, large, unrepaired piece of high quality from the amazing finds here of several years ago.
ex. Ralph Sutcliffe
At 3 cm across, the crystal is large enough to make this overall very balanced specimen a world class example in its size range. The crystal has, despite its age (over 125 years old), only a few very minor dings and one slight contact atop (where it grew against something that made a minor dimple - but that is not damage per se). It has exceptionally sharp 3-dimensional form and is freestanding on the best kind of crystallized matrix you could ask from here (on quartz), and it has brilliant lustre with an unusual slight iridescence to it. This natural iridescent patina proves the piece is au naturale, not cleaned by acids to look bright and stibnite-shiny by modern cleaning methods. Bournonite from the old mid-1800s finds in Cornwall was long considered the world pinnacle of the species by sophisticated collectors, for style and association. Truly, China has produced great bournonites in modern times, but the allure of these old classics still holds. The crystal habit and style is still unique, over 100 years later. Pieces like this were collected from the late 1850s through 1870s, according to books and records I am aware of. Very few of great quality were ever found, and oibviously fewer yet survive to be owned by private collectors, outside of museum holdings. This piece was once in the Ralph Sutcliffe collection of Cornwall Minerals in the 1980s, and later ended up in the collection of George Elling. For what is is, this is a hard thing to beat, and i would argue that nothing comparable can be found on the modern market in a normal year.
This is a very old specimen from the noted classics collection of Phil Scalisi, featuring floating crystals of bournonite replaced by the related lead sulfide species, bindheimite. The crystals are mostly doubly-terminated, and show classic bournonite form! Admittedly, "wolchite" isn't the most beautiful pseudomorph on the planet but its still an impressive piece for intellectual interest and for this old locality, an ancient iron mining area located near St Gertraud. I had only ever seen smears and broken bits of such crystals, and compared to them this is a kingly specimen. ex Harvard University Museum
ex. Richard Heck
RARE for the locale, this vuggy matrix of lustrous, battleship gray galena hosts striated, darker gray crystals of bournonite, to 8 mm across. I cannot recall seeing but 2 or 3 Naica bournonites before. The matrix is also filled with glassy and gemmy, colorless fluorite cubes to 3.2 cm across - thus proving the piece is from Naica by its style or I would have thought the bournonite was from elsewhere. The fluorite exhibits a faint green fluorescence. Aesthetic , and displaying the rare association, this is a combo piece that is worth more than the sum of its parts!
ex. Richard Heck
Sharp, relatively large bournonite crystals for this locale are perched on lustrous black sphalerite crystals, associated with a druse of,sparkling, brassy yellow pyrite and minor drusy, white quartz. A few of the bournonite crystals are also doubly terminated. They are sharp and shwo the striations characteristic of this locale - once one of the world's great sources for this species
ex. Richard Heck
Bournonite is very rare at this locality. This is a solid , bright metallic mass of galena crystals to 2 cm across, with varying luster from satiny to splendent. Scattered on the galena are lustrous and translucent, light pastel-purple fluorite crystals, to 1.8 cm across. Small bournonite crystals, exhibiting the classic cog-wheel pattern so desirable, are present on some galena crystals, and reach 1 cm across. Additioinally,there are pods of splendent, brassy yellow, drusy, pyrite. A neat combo specimen, from this old classic locale !
7.3 x 7 x 2.5 cm. Superb plate completely covered with excellent 1 cm Bournonite crystals intermixed with a small amount of well-crystallized pyrite. The Bournonites have striated faces with a silky to mirror-like metallic luster, and the terminations show the same variation in luster. You can see the development of Bournonite’s classic cogwheel habit. this is a MAJOR Mexican bournonite specimen. It is old, fine, and large - with also large crystals for the locale.
3.9 x 3.7 x 1.7 cm. There was a find of this relatively rare copper sulfosalt about 6 years ago at Machacamarca, and this piece is definitely one of the more unique to come out in this size range. This piece features several, attractive, sharp, lustrous, tabular, silvery-grey color crystals of Bournonite on Siderite and Quartz matrix. This is actually an attractive specimen (especially for this mine), and displays very well.
2.4 x 2.0 x 1.9 cm. A nifty, showy and UNUSUAL combination specimen from the Yaogangxian Mine of China of lustrous, metallic bournonite blades attractively attached to transparent, lustrous, interpenetrating, dark purple fluorite cubes, which are included with bismuthinite needles.
6.4 x 5.7 x 4.0 cm. This is one of the more aesthetic specimens of Bournonite that I have had from Bolivia. This piece consists of an attractive, sharp, tabular, silvery-grey color crystal sitting atop micro Quartz matrix. This specimen is from the find about 6 years ago, when some of the finest Bolivian Bournonites were collected.
2.5 x 1.9 x 1.6 cm. For overall quality, this is a very good Bournonite from Bolivia. With the new Chinese Bournonites out on the market, the Bolivian pieces get lost in the mix because the Chinese pieces are simply everywhere right now. Virtually every piece of Chinese Bournonite that I’ve seen feature excellent, lustrous, prismatic crystals, but the large majority of them are very badly damaged (most crystals are bashed on every side), so comparatively, this Bolivian specimen is just stunning because the quality is much better. There was a find of this relatively rare lead copper antimony sulfosalt about 6 years ago at Machacamarca, and this piece is one of the better quality pieces found, especially for a crystal this size. This piece features an attractive, sharp, doubly-terminated, tabular, bright, metallic, lustrous, silvery-grey color "cogwheel"-shaped crystal on minor Quartz. The Bournonite is complete on all sides and is simply one of the most attractive specimens of this material that I’ve seen recently. This material was found in very small quantities from Bolivia in such fine crystals.
7.5 x 7.2 x 4.3 cm. Sharp, battleship-gray, twinned bournonite crystals richly and attractively cover the upper portion of this fine combination specimen, along with black wurtzite crystals. Ex. Scott Williams and George Elling Collections.
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