Snowflake Obsidian
Volcanic glass with Cristobalite inclusions (70–75% SiO2)
Igneous
Category
Man Made Glass Mineral Simulant
Browse man made glass mineral simulant specimens identified by the Rock Identifier community.
Obsidian
Volcanic glass (SiO2 - Silicon Dioxide with impurities)
igneous
Marble
Marble (metamorphosed limestone/dolostone). Predominantly composed of Calcite (CaCO3) for marble derived from limestone, or Dolomite (CaMg(CO3)2) for marble derived from dolostone.
Metamorphic Rock
Quartz (Clear Quartz/Rock Crystal)
Silicon Dioxide (SiO2)
mineral
Quartz Pebble (Chert/Chalcedony)
Silicon Dioxide (SiO2)
mineral
Snowflake Obsidian
Volcanic glass containing Spherulite inclusions (primarily Cristobalite, SiO2)
igneous
Borosilicate Glass (Manufactured)
SiO2 + B2O3 (Silicon dioxide and Boron trioxide)
Synthetic/Amorphous Solid
Quartz
Silicon Dioxide (SiO2)
mineral
Fluorite
Calcium fluoride (CaF2)
mineral
Obsidian
Extrusive igneous volcanic glass (rich in SiO2)
igneous
Pink Feldspar (Orthoclase)
Orthoclase Feldspar (KAlSi3O8)
mineral
Obsidian
Volcanic glass
igneous
Gold (Elemental Metal)
Gold (Au)
Mineral
Obsidian
Volcanic glass (SiO2 - Silicon Dioxide)
Igneous
Sandstone (with potential mineral staining/concretions)
Arenite (SiO2 based)
sedimentary
Quartz Pebbles
Silicon Dioxide (SiO2)
mineral
Gold
Aurum (Au)
Mineral (Metal)
Obsidian
Volcanic glass (SiO2-rich extrusive igneous rock)
igneous
Quartz (Clear Quartz/Rock Crystal)
Silicon Dioxide (SiO2)
mineral
Amethyst (Raw Quartz)
Silicon Dioxide (SiO2) with iron impurities
mineral
Quartz on Schist
Silicon Dioxide (SiO2) on Foliated Metamorphic Rock
metamorphic
Green Fluorite (likely synthetic or heat-treated for jewelry)
Calcium Fluoride (CaF2)
mineral
Quartz Geode (with possible Manganese or Goethite coating)
Silicon Dioxide (SiO2)
mineral
Black Obsidian
Volcanic Glass (SiO2)
igneous
Quartz (Clear Quartz/Rock Crystal)
Silicon Dioxide (SiO2)
mineral
Quartz (Milky/Rose variety)
Silicon Dioxide (SiO2)
mineral
Quartz (Milky to Clear)
Silicon Dioxide (SiO2)
mineral
Snowflake Obsidian
Spherulitic Obsidian (primarily SiO2)
igneous
Black Obsidian
Obsidian (Volcanic Glass)
igneous
Quartz / Common Opal Transition
Silicon Dioxide (SiO2)
mineral
Pumice or Tufa/Travertine
Pumice (if igneous) or Calcareous Tufa (if sedimentary)
igneous/sedimentary
Quartz (Druzy)
Silicon Dioxide (SiO2)
mineral
Chert (variant Flint/Jasper)
Microcrystalline Opaline Silica (SiO2)
sedimentary
Milky Quartz Pebble
Silicon Dioxide (SiO2)
mineral
Black Obsidian
Obsidian (Volcanic Glass), primarily SiO2 (Silicon Dioxide)
igneous
Quartzite and Jasper Pebbles
Quartzite (re-crystallized Quartz) and Cryptocrystalline Quartz (SiO2)
metamorphic
Slag Glass (Cullet Glass)
Amorphous Silica (Industrial byproduct)
mineral
Quartz
Silicon Dioxide (SiO2)
mineral
Muscovite Mica
Muscovite (Potassium Mica) KAl2(AlSi3O10)(OH)2
Mineral
Slag
Ferrous slag (by-product of iron smelting)
Mineraloid / Anthropogenic
Obsidian
Obsidian (Volcanic Glass)
igneous
Glazed Ceramic Tile
Fused Silicate-Clay composite
Synthetic (Man-made material mimicking natural stone)