Calcite
Calcium Carbonate (CaCO3)
Category
Browse sedimentary or igneous (secondary formation) specimens identified by the Rock Identifier community.
Calcite
Calcium Carbonate (CaCO3)
Gneiss
Gneiss (High-grade metamorphic rock)
Shale or Slate with Quartz Veins
Shale (fine-grained clastic sedimentary rock) or Slate (low-grade metamorphic rock formed from shale) with Quartz (SiO2) veins
Moss Agate
Moss Agate (a variety of Chalcedony, SiO ₂)
Peridot (Olivine)
Olivine, (Mg,Fe)2SiO4
Amethyst
SiO2 (Silicon Dioxide) - a variety of Quartz
Limonite (Yellow Ochre)
Limonite (Hydrated iron(III) oxide-hydroxide, FeO(OH)·nH2O)
Ferruginous Quartz
Silicon Dioxide (SiO2) with Iron Oxide inclusions
Iron-stained Quartz
Silicon Dioxide with Iron Oxide (SiO2 with Limonite/Hematite impurities)
Gold Nugget
Native Gold (Au)
Larimar
Blue Pectolite (NaCa2Si3O8(OH))
Chrysocolla
Hydrated copper phyllosilicate mineral (Cu,Al)2H2Si2O5(OH)4·n(H2O)
Eye Agate
Silicon Dioxide (SiO2) - Banded Chalcedony
Quartzite with Quartz Veining
Quartzite (primarily SiO2)
Ferruginous Quartz (Iron-stained Quartz)
Silicon Dioxide with Iron Oxide (SiO2 + Fe2O3)
Turquoise (likely stabilized or Howlite/Magnesite imitation)
Hydrated phosphate of copper and aluminium, CuAl6(PO4)4(OH)8·4H2O
Green Apophyllite on Stilbite
Fluorapophyllite-(K) [(KCa4Si8O20F)·8H2O] and Stilbite [NaCa4(Si27Al9)O72·28H2O]
Ferruginous Quartz
SiO2 (Silicon Dioxide) with Iron Oxide inclusions (FeO(OH) / Fe2O3)
Malachite
Malachite (Cu2CO3(OH)2)
Silver (Jewelry form)
Native Silver (Ag)
Chlorastrolite (Isle Royale Greenstone)
Chlorastrolite (Pumpellyite-(Mg,Fe2+): Ca2MgAl2(Si2O7)(SiO4)(OH)2∙H2O)
Azurite and Malachite
Azurite (Cu3(CO3)2(OH)2) and Malachite (Cu2(CO3)(OH)2)
Blue Slag Glass
Amorphous Silica (Industrial byproduct)
Green Aventurine
Aventurine Quartz (SiO2 + K(Al,Cr)2AlSi3O10(OH)2)
Yellow Agate
Silicon Dioxide (SiO2)
Golden Healer Quartz
Ferruginous Quartz (SiO2 with Fe2O3 inclusions)
Pearl
Aragonite and Calcite (CaCO3) with Conchiolin
Quartz (Milky/Common)
Silicon Dioxide (SiO2)
Man-made Slag (Industrial Byproduct)
Anthropogenic Glassy Residue
Fluorite
Fluorite (Calcium Fluoride, CaF2)
Milky Quartz
Quartz (Silicon Dioxide - SiO2)
Epidote
Ca2(Al2,Fe3+)(SiO4)(Si2O7)O(OH)
Moldavite
Silica glass with small amounts of aluminum, iron, and other elements
Carnelian
Carnelian (a variety of Chalcedony, SiO2)
Gneiss (Metamorphic Cobble)
Gneiss
Emerald in Matrix
Beryl (Be3Al2Si6O18) containing Chromium/Vanadium impurities
Agate (Lace Agate Geode Slice)
Silicon Dioxide (SiO2)
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
Mica Schist (with Golden/Biotite inclusions)
K(Mg,Fe)3AlSi3O10(F,OH)2 (Biotite), KAl2(AlSi3O10)(F,OH)2 (Muscovite)
Blue Lace Agate
Chalcedony (a form of Quartz) - SiO2
Gneiss
Gneiss (Metamorphic high-grade)
Gneiss
High-grade Metamorphic Gneiss