Black Obsidian
Volcanic Glass (SiO2 + impurities)
Category
Browse sedimentary or metamorphic (low grade) specimens identified by the Rock Identifier community.
Black Obsidian
Volcanic Glass (SiO2 + impurities)
Desert Rose
Gypsum (CaSO4·2H2O) or Barite (BaSO4) inclusions in sand
Bull Quartz
Quartz (Silicon Dioxide - SiO2)
Clear Quartz (Double Terminated)
Silicon Dioxide (SiO2)
Chrysocolla in Matrix
Chrysocolla (Cu,Al)2H2Si2O5(OH)4·nH2O
Apache Tear (Obsidian)
Volcanic glass (SiO2 - Silicon Dioxide)
Beryl (Aquamarine) in Matrix
Beryllium aluminum silicate (Be3Al2(SiO3)6)
Apache Tears (Obsidian)
Hydrated Volcanic Glass (Amorphous SiO2 + H2O)
Quartz Pebble
Silicon Dioxide (SiO2)
Dioptase
Dioptase (CuSiO3 · H2O)
Shungite
Shungite (Amorphous Carbon)
Tektite (Indochinite)
Tektite (High-silica natural glass)
Porphyritic Rhyolite (Red Rhyolite)
Rhyolite (Porphyry)
Cobaltian Calcite
Cobalt-bearing Calcite (Ca,Co)CO3
Rose Quartz
Silicon Dioxide (SiO2) with trace amounts of Titanium, Iron, or Manganese
Rose Quartz and Milky Quartz
Silicon Dioxide (SiO2)
Amethyst
Silicon Dioxide with Iron impurities (SiO2)
Quartz (Milky Quartz)
Silicon Dioxide (SiO2)
Olivine
Olivine group (Mg, Fe)2SiO4
Aquamarine with Quartz
Beryl (Be3Al2Si6O18) with Quartz (SiO2)
Fluorite (tumbled pebble)
Calcium Fluoride (CaF2)
Chrysocolla on Matrix
Hydrated copper phyllosilicate (Cu,Al)2H2Si2O5(OH)4·nH2O
Diamond (in Matrix)
Carbon (C)
Olivine (Peridotite)
(Mg,Fe)2SiO4 (Magnesium Iron Silicate)
Clear Quartz (Rock Crystal)
Silicon Dioxide (SiO2)
Yellow Ochre / Limonite
Limonite (Hydrated Iron(III) Oxide-Hydroxide, FeO(OH)·nH2O)
Sea Glass (Kelly Green)
Amorphous Silica (Silicon Dioxide with Iron/Chromium additives)
Agate (Moss or Lake Superior type)
Silicon Dioxide (SiO2) - Cryptocrystalline Quartz
Chrysocolla
Chrysocolla (Cu2-xAlx(H2-xSi2O5)(OH)4·nH2O)
Silver (Native Element)
Ag (Native Silver), with minor Copper (Cu)
Smoky Quartz
Silicon Dioxide (SiO2)
Azurite with Malachite
Azurite: Cu3(CO3)2(OH)2 / Malachite: Cu2CO3(OH)2
Tahitian Black Pearl
Biogenic Calcium Carbonate (Aragonite/Conchiolin Mixture), CaCO3
Fluorite (Purple variety)
Calcium Fluoride (CaF2)
Diamond (in a gold ring setting)
Carbon (C)
Peach Moonstone
Orthoclase Feldspar ((K,Na)AlSi3O8)
Chrysocolla
Hydrated copper silicates (Cu,Al)2H2Si2O5(OH)4·nH2O
Clear Quartz
Silicon Dioxide (SiO2)
Amethyst and Citrine (Quartz variants)
Silicon Dioxide (SiO2)
Obsidian
Obsidian (principally SiO2 - Silicon Dioxide)
Chrysocolla on Matrix
Hydrated copper phyllosilicate (Cu,Al)2H2Si2O5(OH)4·nH2O
Amethyst (Tumbled)
Quartz (Silicon Dioxide, SiO2) with iron impurities