2.2" Roselite Crystals on Cobaltoan Calcite - Morocco

Cobaltoan calcite, also known as cobaltocalcite, is one of many different varieties of calcite, forming with a chemical composition of (Ca,Co)CO3. It crystallizes in a trigonal crystal system and forms rhombohedral or scalenohedral crystals. These crystals tend to display a pink color that ranges anywhere from a pinkish-salmon to a hot pink.

Roselite is an arsenate mineral in the monoclinic crystal system. It gained its name not from the rose color it generally exhibits, but was in fact named in honor of a German mineralogist by the name of Gustav Rose. However, the name is quite fitting, since roselite typically displays a vitreous rose-red to pink color. Darker crystals have been known to frequently display marked color zoning due to variations in molecular composition.

Roselite has the chemical formula Ca2Co(AsO4)2 · 2H2O, meaning it contains arsenic. While it doesn't pose an immediate health risk from purely handling, ingestion in significant amounts and/or crushing and inhaling roselite can be toxic. For this reason, we suggest washing hands after handling and keeping out of reach of children.