5.49 ct. Coquimbite
Color: Medium Orange-Purple / Yellowish-Orange
Clarity: Transparent
Origin: Alcaparrosa Mine, Sierra Gorda, Antogasta, Chile
Cut: Square Cushion
Treatments: None
Measurements: 12.3 mm
Well, what does one say about this one? The sheer existence of a faceted, gemmy Coquimbite in excess of 5 carats is testament to the creativity and talent in the rare stone market. These are essentially impossible to facet - hardness of 2.5, brittle, cleavage - oh yes, and water soluble. Yet, the rather lovely purple color made us wonder about the possibility of such a gem when this Chilean find started appearing with mineral dealers a few years ago.
The resulting gem is quite significant. For the difficulty of the material, it is beyond exceptionally well done, a true tour-de-force. Custom shape, transparent and a magnificent size. As a hydrated ferric sulfate, Coquimbite can change over time through dehydration and what you see as an orangish color on the edges is the product of this process. There are a few patches of this around the stone but we believe the gem is now relatively stable. We have been holding this one for a few years and believe we have reached equilibrium with this alteration and as long as its stored correctly this one should continue to THE example of a faceted gem of this species. Delightfully esoteric and really quite unreal!