Blue Calcite
Calcium Carbonate (CaCO3)
Category
Browse manufactured glass specimens identified by the Rock Identifier community.
Blue Calcite
Calcium Carbonate (CaCO3)
Chalk / Sedimentary Limestone
Calcium Carbonate (CaCO3) - Biogenic Sedimentary Rock
Chiastolite (Andalusite)
Al2SiO5
Basalt (Water-worn pebble)
Mafic Igneous Rock (primarily Plagioclase feldspar and Pyroxene)
Dumortierite Quartz
Al7(BO3)(SiO4)3O3
Yellow Calcite
Calcium Carbonate (CaCO3)
Kyanite (Purple variety)
Kyanite (Al₂SiO₅)
Aragonite Star Cluster (or Aragonite Sputnik)
Aragonite (Orthorhombic Calcium Carbonate, CaCO3)
Calcite
Calcium Carbonate (CaCO3)
Fuchsite (Green Muscovite in Quartz)
K(Al,Cr)2(AlSi3O10)(OH)2 - Chromium-rich Muscovite
Orange Calcite
Calcite (Calcium Carbonate - CaCO3)
Scoria (Vesicular Basalt)
Vesicular Basalt
Fossiliferous Limestone (Chertified Limestone)
Calcium Carbonate (CaCO3) often replaced by Microcrystalline Silica (SiO2)
Basalt
Basalt
Basalt
Basalt (Mafic Extrusive)
Fluorite Octahedron
Fluorite (Calcium Fluoride, CaF2)
Chert
Chert (Microcrystalline Silica, SiO2)
Optical Calcite (Iceland Spar)
Calcite (Calcium Carbonate, CaCO3)
Green Kyanite
Kyanite (Al2SiO5)
Fluorite
Calcium Fluoride (CaF2)
Shale or Siltstone
Sedimentary Clastic Rock (Variable mineral composition including quartz and clay minerals)
Limestone
Calcium Carbonate (CaCO3)
Chert (Arrowhead or Projectile Point)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Limestone
Calcium Carbonate (CaCO3)
Limestone
Calcium Carbonate (CaCO3)
Blue Calcite
Calcite (CaCO3)
Green Aventurine
Silicon Dioxide (SiO2) with inclusions of Fuchsite
Aventurine
Silicon Dioxide (SiO2) with inclusions of Fuchsite
Opalite
Synthetic Opalised Glass
Snowflake Obsidian
Spherulitic Obsidian (primarily SiO2 with Cristobalite inclusions)
Obsidian (Black)
Obsidian (High-silica volcanic glass)
Sea Glass (Frosted Glass)
Amorphous Silica (SiO2) with various metal oxide impurities
Sandstone
Sandstone (Clastic Sedimentary Rock)
Metal Alloy (Jewelry)
Not a naturally occurring rock or mineral; likely a metal alloy for jewelry. Possible compositions include sterling silver (92.5% silver, 7.5% copper), or other silver/gold alloys.
Green Slag
Anthropogenic Silicate Glass
Cobalt Blue Slag Glass
Amorphous Silicon Dioxide (anthropogenic) with Cobalt additives
Muscovite Schist
Mica Schist (primarily KAl2(AlSi3O10)(OH)2)
Muscovite Mica (likely on Quartz/Feldspar)
Muscovite - KAl2(AlSi3O10)(OH)2
Muscovite Schist
Mica Schist (KAl2(AlSi3O10)(OH)2)
Quartz with Iron Stains
Quartz (SiO2) with iron oxide/hydroxide staining
Green Aventurine
Aventurine Quartz (SiO2 + Fuchsite mica)
Fossiliferous Limestone
Biogenic Limestone (Calcium Carbonate, CaCO3)