Spinel & Orange Titanite on Calcite Matrix | Natural red UV reactive crystal, mineral specimen from AfghanistanSpinel on calcite from Afghanistan are striking mineral specimens in which well formed spinel crystals sit naturally atop a contrasting white calcite matrix. This specimen also has orange titanite crystals, creating an even more unusual combination. Spinel is often purple pink to red, and features octahedral faces. These rare and aesthetic combinations are typically found in marble and metamorphosed carbonate rocks of regions like the Koksha Valley in