Chert (variations include Flint)
Microcrystalline or cryptocrystalline Quartz (SiO2)
Category
Browse not a natural rock (man made composite) specimens identified by the Rock Identifier community.
Chert (variations include Flint)
Microcrystalline or cryptocrystalline Quartz (SiO2)
Flint
SiO2 (Cryptocrystalline Quartz)
Tumbled blue sodalite (probable)
Sodalite, Na₈(Al₆Si₆O₂₄)Cl₂
Yellow Quartz
SiO2 (Silicon Dioxide)
Smoky Quartz
Silicon Dioxide (SiO2)
Citrine Quartz
Silicon Dioxide (SiO2)
Hemimorphite or Red Quartz
SiO2 (Quartz) / Zn4Si2O7(OH)2·H2O (Hemimorphite)
Smoky Quartz
Silicon Dioxide (SiO2)
Green glassy cabochon, likely dyed or synthetic material
Uncertain; possibly green obsidian, chrysoprase, or synthetic glass
Blue sapphire ring
Corundum, aluminum oxide (Al₂O₃), blue variety colored mainly by iron and titanium
Smoky Quartz (with Iron Inclusions)
Silicon Dioxide (SiO2)
Tumbled goldstone-like quartz pebble
Likely iron-stained quartz or jasper; exact identification requires testing
Chert (specifically White Chert or Flint)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Costume Jewelry Gemstones (Emerald-imitation and semi-precious beads)
BeCuAl6Si6O18 (Beryl structure), frequently simulated by glass or synthetic spinel
Gypsum (Satin Spar / Alabaster variety)
Calcium Sulfate Dihydrate (CaSO4·2H2O)
Smoky Quartz
Silicon Dioxide (SiO2)
Shiva Lingam
Cryptocrystalline Quartz (Jasproid/Chalcedony mix)
Diamond
Diamond (C)
Fossil Sea Urchin (Echinoid)
Echinoidea fossil (often replaced by silica or calcite)
Rounded flint or chert pebble
Microcrystalline quartz (SiO₂), commonly chalcedony with possible impurities
Smoky Quartz
Quartz (Silicon Dioxide, SiO2)
Chert (Flint)
Silicon Dioxide (SiO2)
Quartz (Citrine or Iron-Stained)
Silicon Dioxide (SiO2)
Clear Quartz (faceted) / Diamond Simulant
Silicon Dioxide (SiO2) / Cubic Zirconia (ZrO2)
Polished mahogany obsidian (likely)
Volcanic glass; primarily silica-rich rhyolitic glass (SiO₂), with iron oxides
Fossiliferous Limestone
Biomicrite / Limestone with fossils
Dyed Agate
Agate (Silicon Dioxide, SiO2)
Smoky Quartz
Silicon Dioxide (SiO2)
Quartzite
Metamorphic Quartzite (primarily SiO2)
Dyed Fuchsia Tiger’s Eye
Pseudomorph of Quartz after Crocidolite (SiO2)
Smoky Quartz
Silicon Dioxide (SiO2)
Quartz Pebble
Silicon Dioxide (SiO2)
Smoky Quartz
Silicon Dioxide (SiO2)
Smoky Quartz
Silicon Dioxide (SiO2)
White quartz pebble (likely milky quartz)
Quartz, silicon dioxide (SiO₂)
Moissanite
Silicon Carbide (SiC)
Golden Quartz (Citrine or Iron-stained Quartz)
Silicon Dioxide (SiO2)
Chert (varietal: Flint/Jasper)
Silicon Dioxide (SiO2)
Quartzite
Metamorphic Quartzite (SiO2)
Citrine Quartz
Silicon Dioxide (SiO2) with iron impurities
Smoky Quartz
Silicon Dioxide (SiO2)
Blue faceted gemstones, likely blue sapphire
Corundum (Al₂O₃), blue varieties colored chiefly by iron and titanium