Sandstone (Water-worn Pebble)
Clastic Sedimentary Rock (primarily SiO2)
Category
Browse mineraloid (human made geological specimen) specimens identified by the Rock Identifier community.
Sandstone (Water-worn Pebble)
Clastic Sedimentary Rock (primarily SiO2)
Biotite (Black Mica)
Biotite - K(Mg,Fe)3(AlSi3O10)(OH)2
Fluorite (Green Fluorite)
Fluorite (Calcium Fluoride, CaF2)
Pyrite (Fool's Gold)
Iron Sulfide (FeS2)
Yellow Quartzite (River Stone)
Quartzite (primarily SiO2)
Pink Granite
Phaneritic Felsic Igneous Rock (composed primarily of K-Feldspar, Quartz, and Mica)
Banded Agate (Tumbled)
Agate (Silicon Dioxide, SiO2 - Cryptocrystalline Quartz)
Cloudy Quartz / Quartz Tumble
Silicon Dioxide (SiO2)
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
Siltstone
Siltstone (primarily composed of microcrystalline Quartz and Feldspar)
Green Calcite
Calcite (CaCO3)
Amber
Succinite
Quartz with Iron Oxide Inclusions
SiO2 with Fe2O3 impurities
Gold Nugget
Native Gold (Au)
Granite (Leucogranite)
Felsic Plutonic Rock (Granite)
Chert (Jasper/Flint variety)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Jasper and Basalt (Mixed Breccia or Chert)
Silicon Dioxide (SiO2) with Ferromagnesian silicates
Chert (Nodular)
Microcrystalline Silica (SiO2)
Pyrite (Fool's Gold)
Iron Sulfide (FeS2)
Basalt (Road Gravel)
Aphanitic mafic volcanic rock (various compositions of plagioclase feldspar and pyroxene)
Jasper
Silicon dioxide (SiO2)
Chert (Yellow or Tan Chert)
Silicon Dioxide (SiO2)
Chert (often called Flint when in chalk or limestone)
Silicon Dioxide (SiO₂)
Chert (specifically as a lithic artifact/projectile point)
Chert (Silicon dioxide, SiO2)
Pyrite in Matrix (Commonly called Fool's Gold)
Iron Sulfide (FeS2)
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
Azurite Geode
Azurite (Cu3(CO3)2(OH)2)
Granite
Granite (Felsic Plutonic Rock)
Granite
Granite (Alkali feldspar, Plagioclase feldspar, and Quartz)
Fluorite
Calcium Fluoride (CaF2)
Clear Quartz (Rock Crystal)
Silicon Dioxide (SiO2)
Milky Quartz with Iron Staining
Quartz (Silicon Dioxide, SiO2)
Muscovite Mica
Muscovite (Potassium Aluminum Silicate Hydroxide Fluoride), KAl2(AlSi3O10)(OH,F)2
Gneiss
Gneiss (High-grade Regional Metamorphic Rock)
Amber
Succinite (fossilized resin)
Amber (Burmite)
Fossilized tree resin (Succinite variant)
Amber
Succinite (specifically Baltic Amber) - Formula: C10H16O (approximate)
Specular Hematite (Specularite)
Iron Oxide (Fe2O3)
Yellow Quartz / Quartzite Pebble
Silicon Dioxide (SiO2)
Almandine Garnet
Almandine - Fe3Al2(SiO4)3
Slag (Industrial Byproduct)
Ferro-silicate glass (Slag)
Pyrite
Iron Sulfide (FeS2)