large Dioptase & Calcite

Item Description

Uncommonly large, rich and impressive dioptase on calcite from famous Altyn-Tyube, the Type Locality in Kazakhstan. The dramatically 3-dimensional, vuggy, 360-degree calcite matrix is peppered with rich emerald-green, gemmy and lustrous prisms to 7 mm. Some of the calcite fluoresces orange under LW UV light. The first specimens reached Imperial Russia in St. Petersburg in 1781 and were described as Emeralds. Famed French crystallographer, Rene Just Hauy, correctly analysed and named the mineral in 1797 as Dioptase. See the excellent 2023 Mineralogical Record article in Vol. 54, No.2. 1128 grams or 2.5 pounds mass. Value? Hard to say. Specimens of this size and quality are very seldom on the market. Impressive in size and richness.