Calcite drinking cup in shape of lotus flower, from the tomb of the pharaoh Tutankhamun, discovered in the Valley of the Kings, Thebes, Egypt, North Africa, Africa

Yellowstone River near Calcite Springs, Yellowstone National Park, UNESCO Wortld Heritage Site, Wyoming, United States of America, North America

Yellowstone River near Calcite Springs, Yellowstone National Park, UNESCO World Heritage Site, Wyoming, United States of America, North America

Terraces of calcite travertine forming the Dunn's River Falls, near Ocho Rios, north coast, Jamaica, West Indies, Caribbean, Central America

Colourful pools of calcite deposits formed at Huanglong temple, Huanglong National Park, UNESCO World Heritage Site, Sichuan Province, China, Asia

Colourful pools of calcite deposit frozen at Huanglong National Park, UNESCO World Heritage Site, Sichuan Province, China, Asia

Colourful pools of calcite deposit frozen at Huanglong National Park, UNESCO World Heritage Site, Sichuan Province, China, Asia

Terraces of calcite travertine forming the Dunn's River Falls, near Ocho Rios, on the north coast of Jamaica, West Indies, Caribbean, Central America

Calcium formations, Pamukkale, UNESCO World Heritage Site, Anatolia, Turkey, Asia Minor, Asia

Hot water in pools on calcite terraces deposited by Mammoth Hot Springs, Yellowstone National Park, UNESCO World Heritage Site, Wyoming, United States of America (U.S.A.), North America

Travertine calcite deposits, Minerva Terrace, Mammoth Hot Springs and Terraces, Yellowstone National Park, UNESCO World Heritage Site, Wyoming, United States of America (U.S.A.), North America

Travertine calcite deposits on the Canary Spring terraces, Mammoth Hot Springs and Terraces, Yellowstone National Park, UNESCO World Heritage Site, Wyoming, United States of America, North America

The "Christmas Tree Room" of Florida Caverns State Park, Marianna, Panhandle, Florida, USA

The "Wedding Room" of Florida Caverns State Park, Marianna, Panhandle, Florida, USA

Calcite flowstone formation in the Big Room, Carlsbad Caverns National Park, New Mexico, USA

Limestone Caves at Florida Caverns State Park, Marianna, Panhandle, Florida, USA

A cave explorer stands on rimstone formations in Hang Son Doong, Vietnam.

The Underworld - Photographs from caves all over the world

Colourful Pools Formed By Calcite Deposits, Huanglong, Sichuan Province, China

Calcite alabaster fountain in the courtyard of the National Art Museum; La Paz, La Paz, Bolivia

Colourful Pools Formed By Calcite Deposits, Huanglong, Sichuan Province, China

Colourful Pools Formed By Calcite Deposits, Huanglong, Sichuan Province, China

Colourful Pools Formed By Calcite Deposits, Huanglong, Sichuan Province, China