This Specimen has been sold.
1.4" Cobaltoan Calcite Crystals on Matrix - Congo
This small specimen contains vibrant, pink cobaltoan calcite crystals on matrix, from the Katanga Province of the Democratic Republic of the Congo. Small amounts of green malachite formed in association with the calcite.
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 of which intensity can range anywhere from a pinkish-salmon to a hot pink.
Malachite is a basic copper carbonate with the chemical formula Cu2CO3(OH)2. This mineral is known for its intense green color, along with the wide variety of formations and patterns that it's found in. Malachite can grow in botryoidal masses, stalactitic, and reniform formations, typically as a tight cluster of fanning fibrous needles that make up a seemingly solid mass. As layers continue to stack during formation, a banded pattern can sometimes begin to take shape, which explains the rings in all shades of green that are seen on most polished malachite specimens.