What is Rhodochrosite?
Rhodochrosite is a rose-pink manganese carbonate, prized as a gemstone, ornamental stone and one of the most desirable collector minerals when crystal quality is high.
Mineralogy and crystal structure
Reference formula: MnCO3. Rhodochrosite is trigonal and belongs to the calcite group. Manganese-rich material is pink to red, while iron, calcium and other substitutions can darken or modify the colour. Transparent crystals are rare and valuable. Rhodochrosite is classified with carbonates and has a trigonal crystal system. Typical hardness is 3.5–4 on the Mohs scale and specific gravity is approximately 3.5–3.7.
Colour, lustre and habit
Typical colours include rose-pink, red, white, brown. The usual rhombohedral, scalenohedral, banded habit and vitreous, pearly lustre help describe a specimen, but colour alone is not diagnostic.
Formation and notable localities
Rhodochrosite forms in or is associated with low-temperature hydrothermal veins, manganese deposits, carbonate replacement zones and mine oxidation environments. Important documented localities include Argentina, Colorado in the United States, Peru, South Africa, Romania and China.
The rose-pink classic of mineral collecting
Rhodochrosite bridges three markets: vivid banded slabs, polished cabochons and exceptional transparent crystals. The best pieces are sold through colour, pattern, locality, crystal form and provenance rather than colour alone.
Collecting and care
The mineral is softer than quartz and reacts with acids. Avoid scratches, vinegar and harsh cleaners; clean gently with water and protect banded or cleaved pieces from impact.
