Rhodochrosite

Rhodochrosite is a manganese carbonate that forms in hydrothermal veins associated with silver, copper, and lead ore deposits. The vivid pink to red color comes directly from manganese, an essential component of its chemistry.

The two forms collectors encounter are dramatically different. Banded rhodochrosite (concentric rings of pink and white) forms as stalactites and stalagmites in cavities within ore veins - the Argentine Capillitas Mine produces cross-sections of these stalactites that reveal stunning rose-like banding patterns. Transparent crystalline rhodochrosite is far rarer and forms as well-defined rhombohedral crystals in hydrothermal pockets.

The Sweet Home Mine in Colorado, at 3,200 meters elevation near Alma, produced some of the world's most spectacular rhodochrosite specimens - cherry-red transparent crystals perched on quartz matrix. The Alma King, discovered in 1992, is considered by many to be the finest mineral specimen ever found in North America.

Rhodochrosite is identified by its distinctive pink color, banded or crystalline habit, and carbonate properties (it fizzes in dilute hydrochloric acid). At hardness 3.5-4, it's quite soft and scratches easily.

Distinguish from rhodonite (harder at 5.5-6, no acid reaction, often has black veining), rose quartz (much harder at 7, no banding), and pink calcite (similar hardness and acid reaction, but typically paler). The banded variety with its concentric pink-and-white rings is unmistakable.