Mixed Minerals — Marin Mineral

Mixed Minerals
August 9, 2025 · 11 specimens

R326 - Covellite with Quartz $300 available

Butte, Silver Bow Co., Montana, USA
Miniature - 3.2 x 2.2 x 2.2 cm

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Hexagonal platy crystals of iridescent Covellite on a Quartz crystal covered matrix. While larger foliated masses of Covellite crystals are more commonly seen, my favorite type from the locality are those such as this specimen with distinct individual crystals associated Quartz crystals. The Covellite crystals reach 1cm in size and have a bright blue iridescent color.

R327 - Covellite with Quartz sold

Butte, Silver Bow Co., Montana, USA
Thumbnail - 3.1 x 2.3 x 2.0 cm

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Hexagonal platy crystals of iridescent Covellite with Quartz crystals and Pyrite. While larger foliated masses of Covellite crystals are more commonly seen, my favorite type from the locality are those such as this specimen with distinct individual crystals associated Quartz crystals. The Covellite crystals reach 1.5cm in size and have a bright blue iridescent color.

R331 - Cuprite with Silver, Copper $1,500 available

Rubtsovskiy Mine, Altaiskiy Krai, Siberia, Russia
Thumbnail - 2.5 x 2.2 x 2.2 cm

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Large single Cuprite crystal on Copper and Silver. The Cuprite is sharp and complete, 2.5cm wide. Beautiful large crystal with the added bonus of Copper and Silver. Undamaged, ex. Mike Keim.

R332 - Prehnite, Analcime on Quartz $800 available

Goboboseb Mountains, Brandberg Area, Namibia
Small Cabinet - 5.7 x 1.5 x 1.5 cm

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Glassy, transparent Quartz crystal with Amethyst phantoms and attached Prehnite and Analcime crystals. The Analcime are glassy and jewel-like. Complete and undamaged, this is a special crystal I've held in my collection for over 20 years.

R333 - Turquoise sold

Arizona, USA
Small Cabinet - 6.6 x 3.7 x 0.6 cm

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Cut and polished slab of 'spider-web'(not sure about lapidary nomenclature?) Turquoise from Arizona. Polished on both sides.

R334 - Calcite stalactites sold

Alzada, Carter County, Montana, USA
Small Cabinet - 5.5 x 4.5 x 3.5 cm

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Cluster of translucent orange Calcite stalactites on a tiny amount of limestone matrix. These Calcites are renowned for their unusual form and color and this one does not disappoint with a rich red/orange color and all stalactites intact and undamaged which is hard to come by with this material. This is an excellent example from the locality likely collected in the 1970s.

R335 - Rose Quartz sold

Minas Gerais, Brazil
Cabinet - 5 x 13.5 x 2.5 cm

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Cluster of glassy Rose Quartz crystals from Brazil. Great crystals with classic rose pink coloration. Can be displayed from either side.

R336 - Lazurite ps. Phlogopite $750 available

Ladjuar Medam, Sar-e-Sang, Badakhshan, Afghanistan
Small Cabinet - 7 x 4.8 x 3.0 cm

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Sharp pseudomorph of Lazurite after Phlogopite on marble. The main crystal on top is 3cm wide and complete all around. These are well documented but rare pseudomorphs, and what I like about this one is that there are other partial crystals below the main crystal where you can actually see the central cores of Phologopite surrounded by the Lazurite.

R337 - Acanthite $2,500 available

Imiter mine, Draa-Tafilalet Region, Morocco
Miniature - 4 x 4 x 2.8 cm

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Fine floater cluster of metallic grey Acanthite crystals. The crystals form a 'herringbone' structure in 3 dimensions - the crystals not only go up and down and sideways, they extend outwards from the front and back too. Complete all around and undamaged. Ex. Mike Keim.

R338 - Microlite $600 available

Rutherford Mine, Amelia (Amelia Court House), Amelia County, Virginia, USA
Thumbnail - 1.5 x 1.5 x 1.3 cm

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Mottled brown single Microlite crystal from Amelia Courthouse. This is a large, well-formed single crystal from this historic USA locality.

R339 - Azurite sold

Hanover #2 Mine, Fierro Dist., New Mexico, USA
Thumbnail - 2.3 x 2 x 1.5 cm

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Two sharp floater crystals of Azurite with minor attached Malachite. Deep blue coloration with a somewhat shimmering, velvety surface luster. These are textbook crystals complete all around and undamaged. Old, hard to find thumbnail-sized Azurite specimen.

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