Obsidian and Green Calcite
Volcanic Glass and Calcium Carbonate (CaCO3)
Category
Browse crystal specimens identified by the Rock Identifier community.
Obsidian and Green Calcite
Volcanic Glass and Calcium Carbonate (CaCO3)
Apache Tear
Obsidian (Volcanic Glass), formula: 70–75% SiO2 plus MgO, Fe3O4
Quartz (Milky Quartz)
Silicon Dioxide (SiO2)
Green Aventurine
Silicon Dioxide (SiO2) with Chromium-rich Fuchsite mica
Orange Calcite
Calcium Carbonate (CaCO3)
Mahogany Obsidian
Volcanic Glass with Hematite/Magnetite inclusions
Snowflake Obsidian
Obsidian with Cristobalite inclusions (70-75% SiO2)
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
Obsidian
Volcanic Glass (Amorphous Silicon Dioxide , SiO2)
Milky Quartz
Quartz (Silicon Dioxide - SiO2)
Snowflake Obsidian
Volcanic Glass (SiO2) with Cristobalite inclusions
Citrine Quartz carving
Silicon Dioxide (SiO2)
Rose Quartz and Lepidolite in Pegmatite
Crystalline Silicon Dioxide (SiO2) with Lithium-rich Mica (K(Li,Al)3(Al,Si)4O10(F,OH)2)
Sodalite
Na8(Al6Si6O24)Cl2
Green Quartzite (Aventurine variety)
Silicon Dioxide (SiO2) with inclusions of Fuchsite
Sphalerite with Galena
Zinc Sulfide ((Zn,Fe)S) and Lead Sulfide (PbS)
Mookaite (Mookaite Jasper)
Silicified Radiolarite (SiO2 with iron oxides)
Rhodonite in Matrix
Rhodonite (Manganese Silicate) - (Mn2+,Fe2+,Mg,Ca)SiO3
Ocean Jasper (Orbicular Jasper)
Silicon Dioxide (SiO2) - Variety of Chalcedony/Quartz
Lepidolite
Lepidolite (K(Li,Al)3(Al,Si,Rb)4O10(F,OH)2)
Ocean Jasper Mushroom
Orbicular Jasper (Silicon Dioxide, SiO2 mixed with various impurities)
Sodalite
Sodalite - Na8(Al6Si6O24)Cl2
Red Jasper (Brecciated or Mottled)
Silicon Dioxide (SiO2) with iron oxide inclusions
Green Fluorite (likely synthetic or heat-treated for jewelry)
Calcium Fluoride (CaF2)
Sunstone
Plagioclase Feldspar (Na, Ca)(Al, Si)4O8 with Hematite or Copper inclusions
Mahogany Obsidian
Obsidian with Hematite inclusions (SiO2 + Fe2O3)
Fuchsite in Quartz
K(Al,Cr)2(AlSi3O10)(OH)2 in SiO2
Banded Calcite (Mexican Onyx)
Calcite (Calcium Carbonate, CaCO3)
Dyed Quartz (often sold as 'Blue Quartz' or 'Blue Agate')
Silicon Dioxide (SiO2) with artificial pigment
Mixed Tumbled Stones Collection
Mixed Silicates and Carbonates (Quartz, Amorphous Silica, Carbonates)
Amazonite
K(AlSi3O8), Microcline (potassium feldspar)
Rhodonite
Manganese Silicate (Mn,Fe,Mg,Ca)SiO3
Smoky Quartz
Silicon Dioxide (SiO2) with aluminum impurities
Erythrite
Erythrite (Cobalt Bloom) - Co3(AsO4)2·8H2O
Pyrite
Iron Disulfide (FeS2)
Citrine
Crystalline Quartz (SiO2) with iron impurities
Clear Quartz
Silicon Dioxide (SiO2)
Amethyst
Quartz (Silicon Dioxide with iron impurities) - SiO2
Strawberry Quartz (Lepidocrosite/Hematite-Included Quartz)
Quartz (Silicon Dioxide) with Lepidocrosite or Hematite inclusions (SiO2 + Fe2O3 · nH2O)
Epidote
Epidote {Ca2}{Al2Fe3+}(Si2O7)(SiO4)O(OH)
Granite
Phaneritic Felsic Intrusive Igneous Rock
Orange Calcite
Calcium Carbonate (CaCO3)