Rhodochrosite

Rhodochrosite From Capillitas Mine Catamarca Province Argentina.

Capillitas Mine, located in Argentina's Catamarca Province, is the world's premier locality for banded, gem-quality rhodochrosite. Colloquially called "Inca Rose," it formed in hydrothermal veins over millions of years. It is highly prized for its vibrant raspberry-to-deep-red and white concentric rings. 

• Appearance: Unlike the transparent, crystalized rhodochrosite found in places like Colorado, Capillitas material is typically opaque and found in massive, stalactitic, or botryoidal (grape-like) formations. 
• Formation: The mineral (MnCO₃) is deposited by hot, circulating fluids in Miocene-era volcanic rocks. Slicing these stalactites reveals intricate, bullseye-like, or "flowery" concentric patterns. 
• Collectibility: This variety is highly sought after by lapidaries and mineral collectors. High-quality, deep-red pieces are rare and highly collectible. 
• Exploration: The mine is situated at a rugged 10,000-foot altitude, and major commercial production for these specific banded specimens effectively wound down in the 1970s.