Fluorite (Polished Point/Tower)
Calcium Fluoride (CaF2)
Category
Browse anthropogenic (man made) specimens identified by the Rock Identifier community.
Fluorite (Polished Point/Tower)
Calcium Fluoride (CaF2)
Possible obsidian or slag glass
Volcanic glass, primarily SiO₂; alternatively industrial iron-rich glassy slag
Cubic Zirconia (Simulated Diamond)
Cubic Zirconia (ZrO2)
Opalite
Synthetic Opalized Glass
Opalite
Synthetic Opalite Glass (Silicon Dioxide)
Blue-dyed tumbled quartz or glass imitation
Quartz (SiO₂), appearance possibly enhanced with blue dye; identity uncertain from image
Blue Goldstone
Man-made glass with suspended copper, cobalt, or manganese particles
Polished gemstone tower assortment
Primarily quartz varieties and simulants; apparent amethyst (SiO₂), rose quartz (SiO₂), clear quartz (SiO₂), fluorite (CaF₂), sodalite, malachite, and possibly dyed or composite stones
Quartz crystal (likely clear quartz)
Quartz, silicon dioxide (SiO₂)
Polished black stone, likely black obsidian
Obsidian (volcanic glass), chiefly silica-rich rhyolitic composition
Sandstone Anvil / Nutting Stone
Quartzose Sandstone (Sedimentary Rock)
Pink Tumbled Quartz (Dyed)
Silicon Dioxide (SiO2)
Dyed Crackle Quartz (Green)
Quenching-treated Quartz (Silicon Dioxide, SiO2)
Quartzite (Engineered Stone)
Silicon Dioxide (SiO2) based synthetic composite
Chert Concretion (with typical hematite/limonite staining)
Sedimentary Concretion (SiO2 with FeO(OH)⋅nH2O)
Sandstone Concretion
Clastic Sedimentary Rock (primarily SiO2 with mineral cement)
Pyrite Concretion (Grapestone)
Iron Sulfide (FeS2) Concretion
Black glassy fragment, likely obsidian or industrial glass
Volcanic glass (obsidian), chiefly amorphous SiO₂; identification uncertain from image
Tumbled gray stone, likely quartz-rich pebble
Probable microcrystalline quartz/chalcedony (SiO₂), possibly gray jasper or quartzite
Goldstone (Brown/Gold variety)
Aventurine Glass (SiO2 with Copper inclusions)
Sea Glass
Amorphous silicon dioxide (SiO2) - Man-made glass tumbled by nature
Blue Goldstone
Goldstone (artificial glass)
Milky quartz (likely quartz crystal fragment)
Quartz, silicon dioxide (SiO₂)
Slag Glass
SiO2 (Silicon Dioxide) with impurities
Opalite
Synthetic Glass, SiO2 base with metallic inclusions
Black Obsidian
Amorphous volcanic glass (SiO2 + impurities)
Aura Quartz (Titanium/Gold coated)
Silicon Dioxide (SiO2) with metallic vapor deposition
Polished white chalcedony or quartz pendant
Microcrystalline quartz (chalcedony), SiO₂; exact identification is uncertain from the image
Polished black stone, likely obsidian
Obsidian (volcanic glass; mostly silica-rich rhyolitic composition)
Green obsidian (likely molded or heat-treated glass-like specimen)
Volcanic glass; predominantly rhyolitic composition (silica-rich amorphous SiO₂)
Clear quartz fragment (rock crystal)
Quartz, silicon dioxide (SiO₂)
Blue opal heart cabochon
Common opal, hydrated amorphous silica (SiO₂·nH₂O), likely blue-dyed or synthetic opalite
Aura Quartz
Titanium/Titanium-Gold treated Silicon Dioxide (SiO2)
Red Slag Glass
Amorphous Silica (Industrial byproduct with metallic oxide dopants)
Metal Alloy (Likely Pewter or Sterling Silver)
Not a natural geological specimen; composed of refined metals. If pewter, it's a tin-based alloy. If sterling silver, it's 92.5% silver and 7.5% other metals (usually copper).
Green sea glass or tumbled green quartz (uncertain)
Likely quartz (SiO₂) if natural; alternatively man-made soda-lime glass
Baked-clay ceramic fragment (likely brick or pottery)
Fired clay, primarily aluminosilicate minerals; not a natural rock
Conglomerate
Conglomerate Rock (Paraconglomerate)
Sandstone Concretion
Clastic sedimentary rock (primarily Quartz SiO2)
Green Aventurine
Quartzite with Fuchsite inclusions (SiO2 + K(Al,Cr)2(AlSi3O10)(OH)2)
Botryoidal chalcedony (likely agate/jasper variety)
Microcrystalline quartz, SiO₂
Polished silver sheen obsidian heart
Obsidian (volcanic glass), primarily rhyolitic silica-rich glass