carbonates
Rhodochrosite
Mn(CO3)
- Also known as
- Inca roserosinca
- Crystal system
- trigonal
- Hardness
- 3.5–4 on the Mohs scale
- Lustre
- vitreous
- Colour
- Rose pink to deep red, often banded
- Where it forms
- In hydrothermal veins with silver and lead ores, and as banded cave deposits in Argentina where manganese-rich water dripped for millennia.
- Chiefly from
- Catamarca, ArgentinaColorado, United StatesSouth AfricaPeru
Why it is that colour
Manganese. The banded material forms as stalactitic layers in caves, so the concentric rings are growth rings in the same sense as an agate’s.
Safety
A soft carbonate that dissolves in acid. Safe to handle; not to be put in water for drinking, and easily damaged by cleaning products.
Where it comes from
Argentine banded material and Colorado crystals dominate. The Sweet Home Mine in Colorado, reopened specifically for specimens rather than ore in the 1990s, produced the finest crystals known, including the Alma King.
Historical use
A manganese ore of minor economic importance. The national stone of Argentina.
Recorded as history and attributed where possible. That a stone was used for something establishes that people used it, not that it worked.
What is attributed to it, and since when
The Inca rose name and the story of Inca silver mines are frequently attached to it, and the Argentine deposits are indeed in old workings. But there is no documented pre-Columbian symbolic use, and the stone entered the international market in the twentieth century. Its meanings are modern.
Described, not endorsed. Dating a claim is not the same as assessing it — but an association that first appears in a book published in 1985 is not an ancient inheritance, whatever the label says. A sincere account of feeling better is compatible with the stone doing nothing — see the placebo effect.
Worth knowing
The Sweet Home Mine is an unusual footnote in mining history. It was a silver mine that closed as uneconomic, and in the 1990s it was reopened to mine specimens — the rhodochrosite crystals were worth more than the silver ever had been. Blasting was done with unusual care to avoid shattering the crystals, which reverses the ordinary logic of a mine entirely.
Identity checked against IMA-CNMNC master list, June 2025.