Rhodochrosite

Hardness: 3.5–4 on Mohs scale; Color: Pink, rose-red, cherry-red, yellowish grey, brown; Luster: Vitreous to pearly; Crystal structure: Trigonal; Cleavage: Perfect rhombohedral in three directions; Specific gravity: 3.4–3.7.

Formed in hydrothermal veins of low to moderate temperature, often associated with silver, lead, and copper deposits. It can also form as sedimentary layers in manganese-rich environments or as stalactites in caves. Formations vary greatly in geological age from Precambrian to Cenozoic.

Primary use is as an ornamental gemstone for jewelry (beads, cabochons) and as a highly prized mineral specimen for collectors. It is also a minor ore of manganese, which is used in the production of low-cost stainless steel and aluminum alloys.

Known as 'Rosa del Inca' (Inca Rose) because the Incas believed it was the solidified blood of their former kings and queens. It is the national gemstone of Argentina and the state mineral of Colorado, USA.

Identify in the field by its distinct pink color, white banding (in stalactitic forms), and reaction to warm hydrochloric acid (fizzing). Common worldwide locations include the Capillitas mine in Argentina, the Sweet Home Mine in Colorado, and various mines in South Africa and Peru. Collectors should look for the characteristic 'bacon-strip' banding seen in polished beads.