Snowflake Obsidian
Volcanic glass with Cristobalite inclusions (70–75% SiO2)
Category
Browse sedimentary (man made composite) specimens identified by the Rock Identifier community.
Snowflake Obsidian
Volcanic glass with Cristobalite inclusions (70–75% SiO2)
Granite
Granite (Silicic Intrusive Igneous Rock)
Granite
Granite (phaneritic intrusive igneous rock consisting of quartz, feldspar, and mica)
Granodiorite
Granodiorite (Quartz + Plagioclase + Alkali Feldspar + Biotite/Hornblende)
Amethyst
Amethyst (Silicon Dioxide - SiO2 with Iron impurities)
Fossiliferous Limestone
Limestone (composed primarily of calcite with included fossils CaCO3)
Chalcedony (or a variety of Chalcedony, likely Agate or Jasper)
Chalcedony (SiO₂)
Diorite (Gneissic)
Diorite
Pearl
Aragonite (CaCO3) with Conchiolin
Diabase (Greenstone)
Diabase (Dolerite)
Smoky Quartz
Smoky Quartz (Silicon Dioxide - SiO2)
Lapis Lazuli
Lapis Lazuli (a rock, not a single mineral; primary mineral is Lazurite (Na,Ca)8(AlSiO4)6(S,SO4,Cl)1-2
Pearl
Pearl (Calcium Carbonate with organic conchiolin, CaCO3)
Moonstone
Orthoclase Feldspar ((K,Na)AlSi3O8) with Albite inclusions
Diorite
Phaneritic Intrusive Igneous Rock (composed of Plagioclase feldspar, Hornblende, and Biotite)
Smoky Quartz
Silicon Dioxide (SiO2)
Silver (Jewelry form)
Native Silver (Ag)
Quartz (Pebble)
Quartz (SiO₂)
Diamond (Cluster Ring)
Carbon (C)
Granite
Phaneritic Felsic Intrusive Igneous Rock
Pearl
Aragonite / Calcium Carbonate (CaCO3)
Granite
Phaneritic Plutonic Felsic Rock (SiO2, KAlSi3O8, NaAlSi3O8, CaAl2Si2O8)
Diamond in Kimberlite
Diamond in Kimberlite Matrix (Diamond: C, Kimberlite: complex Potassic Peridotite)
Basalt
Basalt (Mafic volcanic rock)
Moonstone (specifically Rainbow Moonstone / White Labradorite)
White Labradorite (Feldspar Group: (Na,Ca)(Al,Si)4O8)
Marble
Metamorphic Limestone (CaCO3)
Banded Gneiss
Gneiss (pronounced 'nice')
Diamond
Carbon (C)
Rough Diamond
Diamond (pure Carbon, C)
Aventurine
Silicon Dioxide (SiO2) with inclusions of Fuchsite
Basalt
Basalt (comprising Plagioclase feldspar, Pyroxene, and Olivine)
Smoky Quartz Cluster
Smoky Quartz (Silicon Dioxide - SiO2)
Red Jasper
Jasper (Silicon Dioxide with Iron Oxide inclusions, SiO2 + Fe2O3)
Diorite
Diorite
Nephrite Jade
Nephrite
Rough Diamond
Diamond (pure Carbon, C)
Tektite (Indochinite)
Tektite (Amorphous Silica Glass)
Diorite
Diorite (Intermediate intrusive igneous rock)
Natural Pearl (appearing in a jewelry setting)
Calcium Carbonate (mostly Aragonite), CaCO3 with Conchiolin
Granite
Phaneritic Felsic Igneous Rock (primarily Quartz, Feldspar, and Mica)
Granite (Pegmatitic)
Phaneritic Felsic Igneous Rock
Smoky Quartz
Silicon Dioxide (SiO2) with trace aluminum and irradiation