Basalt
Basalt (Mafic volcanic rock)
igneous
Category
Sedimentary (Base), Then Artificial
Browse sedimentary (base), then artificial specimens identified by the Rock Identifier community.
Granite (Alkali-feldspar rich)
Phaneritic Felsic Igneous Rock (Major components: KAlSi3O8, SiO2)
igneous
Vesicular Basalt
Extrusive Mafic Igneous Rock (primarily Plagioclase Feldspar and Pyroxene)
igneous
Basalt
Extrusive mafic igneous rock
igneous
Basalt
Basalt (Mafic volcanic rock)
igneous
Basalt with Peridotite Inclusion
Mafic Volcanic Rock (Extrusive Igneous) with Ultramafic Xenolith
igneous
Basalt
Basalt (Mainly Plagioclase Feldspar and Pyroxene)
igneous
Basalt with Magnetite
Crystalline Basalt (Primarily Plagioclase and Pyroxene) with Magnetite (Fe3O4)
igneous
Diorite
Phaneritic plutonic rock (dominated by plagioclase feldspar and hornblende)
igneous
Andesite
Andesite (Intermediate Extrusive Volcanic Rock)
igneous
Basalt
Basalt (Aphanitic Mafic Igneous Rock)
igneous
Basalt
Basalt (Aphanitic-fine grained mafic igneous rock)
igneous
Basalt
Basalt (Aphanitic Mafic Igneous Rock)
igneous
Slag (Industrial Glass/Metal)
Ferrous slag or Glassy silicate byproduct
Antropogenic rock (Man-made)
Basalt Pebble
Basalt (Mafic Extrusive Igneous Rock)
igneous
Granodiorite Pebble
Granodiorite (Intermediate intrusive igneous rock)
igneous
Unknown Organic Object (likely a berry or fruit)
Not applicable; this is not a geological specimen. If it were a cranberry, its scientific name would be Vaccinium macrocarpon; if a cherry, it would be Prunus avium or Prunus cerasus.
Organic Material (likely a fruit or berry)
Amethyst
Amethyst (Silicon Dioxide with iron impurities), SiO2
mineral
Quartz with Mica (Gneissic or Pegmatitic origin)
Silicon Dioxide (SiO2) with Phyllosilicates (KAl2(AlSi3O10)(F,OH)2)
metamorphic
Asphalt (Bituminous Concrete)
Bituminous Concrete / Pavement
man-made (synthetic rock)
Green Aura Quartz
Silicon Dioxide (SiO2) bonded with metallic vapors (typically Gold, Chromium, or Titanium)
mineral
Limonite (Bog Iron)
Limonite (Hydrated iron(III) oxide-hydroxide) - FeO(OH)·nH2O
mineral
Granite
Phaneritic Igneous Rock (primarily Quartz, Feldspar, and Mica)
igneous
Peacock Ore
Bornite (Cu5FeS4) or Chalcopyrite treated with acid
mineral
Schist
Chlorite-Mica Schist
metamorphic
Mahogany Obsidian
Volcanic Glass with Hematite/Magnetite inclusions
igneous
Moss Agate
Silicon Dioxide (SiO2) with inclusions of Manganese or Iron oxide
mineral
Citrine Quartz
Crystalline Silicon Dioxide (SiO2) with Ferric Iron impurities
mineral
Amethyst
Amethyst (SiO2 - Silicon Dioxide with Iron impurities)
mineral
Bloodstone (Heliotrope)
Chalcedony (SiO2) with inclusions of Iron Oxide or Red Jasper
mineral
Stilbite
Stilbite-Ca (NaCa4(Si27Al9)O72·28H2O)
mineral
Granite Glacial Erratic
Intrusive Phaneritic Felsic Rock (Granite)
igneous
Citrine
Silicon dioxide (SiO2)
mineral
Snowflake Obsidian
Volcanic glass with Cristobalite inclusions (70–75% SiO2)
igneous
Dendritic Agate
Silicon Dioxide with Manganese or Iron Oxide inclusions (SiO2 + Mn/Fe)
mineral
Sagenitic Agate (with Goethite/Rutile inclusions)
Silicon Dioxide (SiO2) with hydrous ferric oxide inclusions
mineral
Granite Pebble
Felsic Plutonic Rock (primarily Quartz, Feldspar, and Mica)
igneous
Basalt (Amygdaloidal)
Amygdaloidal Basalt
igneous
Amethyst
Amethyst (Silicon Dioxide - SiO2 with ferric impurities)
mineral
Amygdaloidal Rhyolite
Rhyolite (felsic volcanic rock) with amygdules
igneous
Labradorite (likely)
(Ca,Na)(Al,Si)4O8
mineral
Diorite
Diorite (Intermediate intrusive igneous rock)
igneous