a Minerals

Calcite over Arsenopyrite from Santa Eulalia District, Aquiles Serdán, Chihuahua, Mexico

Calcite over Aurichalcite from Mapimi, Durango, Mexico

Calcite over Azurite with Malachite pseudomorphs after Azurite over Quartz from M'Ssici, Tinghir, Souss-Massa-Draâ, Morocco

Calcite over Barite from Montreal Mine, Gogebic Iron Range, Iron County, Wisconsin

Calcite over Calcite from Marion City, Linn County, Iowa

Calcite over Calcite from Tsumeb Mine, Otavi-Bergland District, Oshikoto, Namibia

Calcite over Calcite from Tri-State Lead-Zinc Mining District, near Joplin, Jasper County, Missouri

Calcite over Calcite from Buena Tierra Mine, 19th Level, Santa Eulalia Disctrict, Chihuahua, Mexico

Calcite over Calcite from Buena Tierra Mine, 19th Level, Santa Eulalia Disctrict, Chihuahua, Mexico

Calcite over Calcite from Fengjiashan Mine, Daye, Huangshi, Hubei, China

Calcite over Calcite from Skitchewaug Trail Quarry, Springfield, Windsor County, Vermont

Calcite over Calcite from near Fowler, Otero County, Colorado

Calcite over Calcite from Tsumeb Mine, Otavi-Bergland District, Oshikoto, Namibia

Calcite over Calcite from Tsumeb Mine, Otavi-Bergland District, Oshikoto, Namibia

Calcite over Calcite from Lowville, Lewis County, New York

Calcite over Calcite from Lowville, Lewis County, New York

Calcite over Calcite from Lowville, Lewis County, New York

Calcite over Calcite (V-Twinned Crystals) from Santa Eulalia District, Aquiles Serdán, Chihuahua, Mexico

Calcite over Calcite with Pyrite from Kjørholt Mine, Brevik, Porsgrunn, Telemark, Norway

Calcite over Colemanite from Kramer Deposit, Boron, Kern County, California

Calcite over Conichalcite from Mina Ojuela, Mapimi, Durango, Mexico

Calcite over Datolite from Millington Quarry, Bernards Township, Somerset County, New Jersey

Calcite over Datolite from Millington Quarry, Bernards Township, Somerset County, New Jersey

Calcite over Datolite, Prehnite, Actinolite-Chlorite from Millington Quarry, Bernards Township, Somerset County, New Jersey

Calcite over Dioptase from Tsumeb Mine, Otavi-Bergland District, Oshikoto, Namibia

Calcite over Dolomite from Mina de Reocín, Cantabria, Spain

Calcite over Dolomite from P.J. Keating Company Essex Bituminous Quarry, Dracut, Middlesex County, Massachusetts

Calcite over Dolomite Casts from Maramures, Romania

Calcite over Dolomite molds from Tsumeb Mine, Otavi-Bergland District, Oshikoto, Namibia

Calcite over Dolomite on Calcite from Skitchewaug Trail Quarry, Springfield, Windsor County, Vermont

Calcite over Dolomite on Calcite from Skitchewaug Trail Quarry, Springfield, Windsor County, Vermont

Calcite over Dolomite on Calcite from Skitchewaug Trail Quarry, Springfield, Windsor County, Vermont

Calcite over Dolomite on Calcite from Skitchewaug Trail Quarry, Springfield, Windsor County, Vermont

Calcite over Dolomite on Calcite from Skitchewaug Trail Quarry, Springfield, Windsor County, Vermont

Calcite over Dolomite on Calcite from Skitchewaug Trail Quarry, Springfield, Windsor County, Vermont

Calcite over Dolomite on Calcite from Skitchewaug Trail Quarry, Springfield, Windsor County, Vermont

Calcite over Dolomite pseudomorphs after Calcite from Cavnic Mine (Kapnikbanya), Maramures, Romania

Calcite over Dolomite with Hydrozincite from Mina La Cuerre, Rionansa, La Florida, Sierra de Arnero, Cantabria, Spain

Calcite over Fluorite from Minerva Mine, Cave-in-Rock District, Hardin County, Illinois

Calcite over Fluorite from Cave-in-Rock District, Hardin County, Illinois

Calcite over Fluorite from Cave-in-Rock District, Hardin County, Illinois

Calcite over Fluorite from Villabona District, Asturias, Spain

Calcite over Fluorite from Cave-in-Rock District, Hardin County, Illinois

Calcite over Fluorite from Villabona District, Asturias, Spain

Calcite over Fluorite from Minerva #1 Mine, Cave-in-Rock District, Hardin County, Illinois

Calcite over Fluorite from Denton Mine, Harris Creek District, Hardin County, Illinois

Calcite over Fluorite from Minerva #1 Mine, Cave-in-Rock District, Hardin County, Illinois

Calcite over Fluorite from Minerva #1 Mine, Cave-in-Rock District, Hardin County, Illinois

Calcite over Fluorite from Denton Mine, Harris Creek District, Hardin County, Illinois

Calcite over Fluorite and Barite from Minerva #1 Mine, Cave-in-Rock District, Hardin County, Illinois

Calcite over Fluorite and Quartz from Santa Eulalia District, Aquiles Serdán, Chihuahua, Mexico

Calcite over Fluorite, Galena, Sphalerite from Madan District, Rhodope Mountains, Bulgaria

Calcite over Fluorite, Sphalerite, Pyrite from Naica District, Saucillo, Chihuahua, Mexico

Calcite over Fluorite-Barite from Moscona Mine, Villabona District, Asturias, Spain

Calcite over Galena, Quartz, Sphalerite from Borieva Reka Mine, Madan District, Rhodope Mountains, Bulgaria

Calcite over Limonite Stalactites from El Potosi Mine, Level 16, Santa Eulalia District, Aquiles Serdán, Chihuahua, Mexico

Calcite over Limonite Stalactites from Mina el Potosí, Level 16, Santa Eulalia District, Aquiles Serdán, Chihuahua, Mexico

Calcite over Malachite from Concepción del Oro, Zacatecas, Mexico

Calcite over Malachite from Zacatecas, Mexico

Calcite over Malachite from Silverton Mine, Courtland-Gleeson District, Cochise County, Arizona

Calcite over Malachite from Tsumeb Mine, Otavi-Bergland District, Oshikoto, Namibia

Calcite over Marcasite and Sphalerite from Shullsburg District, Lafayette County, Wisconsin

Calcite over Mimetite from Santa Eulalia District, Aquiles Serdán, Chihuahua, Mexico

Calcite over Natrolite from Millington Quarry, Bernards Township, Somerset County, New Jersey

Calcite over Prehnite from Weldon Quarry, Scotch Plains, Somerset County, New Jersey

Calcite over Prehnite from Prospect Park Quarry, Prospect Park, Passaic County, New Jersey

Calcite over Prehnite from Millington Quarry, Bernards Township, Somerset County, New Jersey

Calcite over Pyrite from Road cut, Shelburne Falls, Franklin County, Massachusetts

Calcite over Pyrite from Casapalca District, Huarochiri Province, Lima Department, Peru

Calcite over Quartz from Tsumeb Mine, Otavi-Bergland District, Oshikoto, Namibia

Calcite over Quartz from Coronation Lode, Levant Mine, Cornwall, England

Calcite over Quartz from LaFarge Quarry, Ravena, Albany County, New York

Calcite over Quartz pseudomorphs after Anhydrite from Prospect Park Quarry, Prospect Park, Passaic County, New Jersey

Calcite over Quartz with Pyrite from Freiberg, Saxony, Germany

Calcite over Rosasite from Silver Bill Mine, Courtland-Gleeson District, Cochise County, Arizona

Calcite over Rosasite with Goethite from Omega Mine, Helvetia District, Pima County, Arizona

Calcite over Sphalerite from Elmwood Mine, Carthage, Smith County, Tennessee

Calcite over Sphalerite and Marcasite from American Zinc Mine, Shullsburg District, Lafayette County, Wisconsin

Calcite over Sphalerite with Bitumen from Elmwood Mine, Carthage, Smith County, Tennessee

Calcite over Sphalerite, Pyrite, Chalcopyrite from Trepca District, 10 km east of Kosozska Mitrovica, Kosovo

Calcite over stalactitic Aragonite from Guilin, Guangxi, China

Calcite over Stellerite from Sokolovskiy Mine, Rudnyy, Kustanay Oblast, Kazakhstan

Calcite over Stibnite, Galena and Realgar from Baia Sprie (Felsöbánya), Maramures, Romania

Calcite over Stilbite from Moore's Station Quarry, 44 km northeast of Philadelphia, Mercer County, New Jersey

Calcite over Stilbite from Moore's Station Quarry, 44 km northeast of Philadelphia, Mercer County, New Jersey

Calcite over Stilbite from Chimney Rock Quarry, Bound Brook, Somerset County, New Jersey

Calcite over Wulfenite from Mammoth Mine, Tiger, Arizona

Calcite pseudomorph after Anhydrite with Dolomite and Sphalerite from Chihuahua, Mexico

Calcite pseudomorph after Aragonite from Natural cave found in Northern Lights Mine, Mineral County, Nevada

Calcite pseudomorph after Aragonite from Monolith Quarry, Albany County, Wyoming

Calcite pseudomorph after Aragonite on Fluorite from Cave-in-Rock, Hardin County, Illinois

Calcite pseudomorph after Barite with Quartz from (Goodfro Mine), Ouray County, Colorado

Calcite pseudomorph after Carletonite with Quartz overgrowth from Poudrette Quarry, Mont Saint-Hilaire, Québec, Canada

Calcite pseudomorph after Glauberite from Camp Verde, Camp Verde, Arizona

Calcite pseudomorph after Glauberite from Camp Verde, Camp Verde, Arizona

Calcite pseudomorph after Glauberite from Camp Verde, Yavapai County, Arizona

Calcite pseudomorph after Halite from Glass Mountains, 13 km northwest of Fairview, Major County, Oklahoma

Calcite pseudomorph after Ikaite from Mono County, California

Calcite pseudomorph after Shortite from Westvaco Mine, Green River Formation, west of Green River, Sweetwater County, Wyoming (Type Locality for Shortite)

Calcite pseudomorph after Shortite from Westvaco Mine, Green River Formation, west of Green River, Sweetwater County, Wyoming (Type Locality for Shortite)

Calcite pseudomorphs after Aragonite from Raura District, Cajatambo Province, Peru

Calcite pseudomorphs after Aragonite from Las Animas, Bent County, Colorado

Calcite pseudomorphs after Aragonite from Johnby Quarry, near Penrith, Cumbria, England

Calcite pseudomorphs after Aragonite from Owl Canyon, Larimer County, Colorado

Calcite pseudomorphs after Glauberite from Chihuahua, Mexico

Calcite pseudomorphs after Glauberite from Chihuahua, Mexico

Calcite pseudomorphs after Glauberite from Camp Verde Salt Mine, Beaver Creek, Yavapai County, Arizona

Calcite pseudomorphs after Glauberite from Camp Verde, Yavapai County, Arizona

Calcite pseudomorphs after Glauberite from Camp Verde, Yavapai County, Arizona

Calcite pseudomorphs after Glauberite from Camp Verde, Beaver Creek, Yavapai County, Arizona

Calcite pseudomorphs after Glauberite from Camp Verde Mine, Yavapai County, Arizona

Calcite pseudomorphs after Glauberite from Camp Verde Mine, Yavapai County, Arizona

Calcite pseudomorphs after Glauberite from Camp Verde Mine, Yavapai County, Arizona

Calcite pseudomorphs after Ikaite from Bielo More, Kola Peninsula, Russia

Calcite pseudomorphs after Ikaite from Olenitsa, Kola Peninsula, Russia

Calcite pseudomorphs after Ikaite (Thinolite formation) from Mono Lake, Mono County, California

Calcite pseudomorphs after Natrolite from Upper New Street Quarry, Paterson, Passaic County, New Jersey

Calcite pseudomorphs after Ulexite from Boron Open Pit, Extension 22S, Boron, Kern County, California

Calcite scepter-shaped formation coated with Quartz from Planalto, Alto Uruguai, Brazil

Calcite Septarian from Orderville, Kane County, Utah

Calcite Stalactite from Lion Hill District, Tooele County, Utah

Calcite Stalactite from Wyandotte Cave, Crawford County, Indiana

Calcite Stalactite (secondary formation) from Bisbee, Warren District, Cochise County, Arizona

Calcite Stalactite (secondary formation) from Bisbee, Warren District, Cochise County, Arizona

Calcite stalactites from cave encountered during highway construction near Flagstaff, Coconino County, Arizona

Calcite stalactitic formation from Tsumeb Mine, Otavi-Bergland District, Oshikoto, Namibia

Calcite Twin from Thomasville, Pennsylvania

Calcite twin from Tri-State District, Baxter Springs, Kansas

Calcite Twin from Mina La Cuerre, Rionansa, La Florida, Sierra de Arnero, Cantabria, Spain

Calcite Twin and Native Copper from National Mine, Rockland, Ontonagon County, Michigan

Calcite twin crystals from Egremont, West Cumberland Iron Mining District, Cumbria, England

Calcite Twin on Dolomite from Mina La Cuerre, Rionansa, La Florida, Sierra de Arnero, Cantabria, Spain

Calcite twin with Datolite from Barranca del Cobre, Aurora Mine, Chihuahua, Mexico

Calcite twin with Pyrite from Naica District, Saucillo, Chihuahua, Mexico

Calcite twinned crystals from Bigrigg Mine, Egremont, Cumbria, England

Calcite twinned crystals from Thomasville Crushed Stone Quarry, Jackson Township, York County, Pennsylvania

Calcite twinned crystals from Elmwood Mine, Carthage, Smith County, Tennessee

Calcite twinned crystals from Elmwood Mine, Carthage, Smith County, Tennessee

Calcite twinned crystals on Amethyst Quartz from Alto Uruguai, Rio Grande do Sul, Brazil

Calcite twinned crystals with Marcasite inclusions from Linwood Mine, Buffalo, Scott County, Iowa

Calcite twins from Laurel Hill (Snake Hill) Quarry, Secaucus, Hudson County, New Jersey

Calcite twins from Laurel Hill (Snake Hill) Quarry, Secaucus, Hudson County, New Jersey

Calcite Twins from Sokolovskoe Iron Mine, west of Rudnyym, Kustany Oblast, Kazakhstan

Calcite Twins from Mina La Cuerre, Rionansa, La Florida, Sierra de Arnero, Cantabria, Spain

Calcite Twins from Mina La Cuerre, Rionansa, La Florida, Sierra de Arnero, Cantabria, Spain

Calcite Twins from Mina La Cuerre, Rionansa, La Florida, Sierra de Arnero, Cantabria, Spain

Calcite var. Butterfly Twin from Devil's Corral, near Black Rock Desert, Humboldt County, Nevada

Calcite var. Butterfly Twin from Devil's Corral, near Black Rock Desert, Humboldt County, Nevada

Calcite var. Butterfly Twin from Devil's Corral, near Black Rock Desert, Humboldt County, Nevada

Calcite var. Butterfly Twin from Devil's Corral, near Black Rock Desert, Humboldt County, Nevada