Calcite var. Cobaltian with Kolwezite
Mupine Mine, Kolwezi, Katanga, Democratic Republic of Congo
Small Cabinet, 7.7 x 5.5 x 5.4 cm
Ex. Jack Halpern; Dr. Robert Lavinsky

Cobaltian calcite at its best has the most stunning color in the mineral world, to my taste (and Jack shares it, as he pursued these aggressively and they were over-represented in his collection!) This specimen was among Jack's top 3 of 9 of these gorgeous cobaltian calcites he had at the peak size of the collection, and I begged him for just one for myself back in the early 2000s as I was strongly collecting calcites. This was traded out to me at that time and has been in my own calcite collection. I collected calcite since the mid-1980s, and I had always dreamed of owning a good one of these! I have since mostly deaccessioned my calcites as I graded my old collection into Chinese-specific minerals the last 20 years - but I KEPT this piece all this time. His suite of these was beautiful, and as a color aficionado, they were among his favorite toys - for obvious reasons when you look at these photos. This piece features a proud, upright 5.5 cm-tall crystal at the edge of a mountainous quartz matrix, and with a bit of dark green kolwezite as an accent to the side. Jack bought this directly from Ken Roberts in the early 1990s, as Ken had a number of them and was at the time located in the San Francisco Bay Area near Jack. I always felt that the combination of color, crystal size and placement, and the interesting matrix that displays the crystal made this a very impactful piece, and I have had the pleasure to keep it in what remains of my childhood and early calcite collection, all these years. For those new to seeing these, all I can say is that in person, the color is surreal and you would assume it to be the fake product of a chemistry experiment - there is no color in minerals like these at their best! Modern material from Morocco is also beautiful, but different. These are still the standard, and I am not aware of many out in the public at this late date after nearly 30 years since they were found.

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