Almost all caves are limestone, with light- colored white to beige stalactites and stalagmites. Other unique cave deposits include vivid pink rhodochrosite stalactities in Argentina, deep green banded malachite formations in Republic of Congo and exotic specimens such as goethite from Spain.
Calcite, Mapimí, Durango, Mexico (3 inch x 7 inch).
Rhodochrosite: Capillitas Mine, Catamarca, Argentina (cut and polished) (9 inch x 16 inch). Photo courtesy Michael J. Bainbridge.
Malachite, azurite and calcite, Bisbee, Cochise County, Arizona (3 inch x 3 ½ inch).
Calcite, Alzada, Carter County, Montana (3 ¼ inch x 4 ¾ inch).
Malachite, Shilu Mine, Yangjiang Prefecture, Guangdong Province, China (4 ¾ inch x 7 inch). Photo courtesy Michael J. Bainbridge.
Smithsonite, Masua Mine, Iglesias, Sardinia, Italy (1 ¾ inch x 2 inch). Photo courtesy Michael J. Bainbridge.
Aragonite, Sounion Area, Lavrion District, Attikí Prefecture, Greece (3 inch x 4 ½ inch). Photo courtesy Michael J. Bainbridge.
Goethite, Filon Sur open pit mine, Tharsis, Andalusia, Spain (5 ½ inch x 7 inch).