Agate
Chalcedony (SiO2)
Category
Browse industrial byproduct (anthropogenic rock) specimens identified by the Rock Identifier community.
Agate
Chalcedony (SiO2)
Rough Blue Diamond
Carbon (C)
Corundum (Ruby Variety)
Corundum (Al2O3)
Anthracite Coal
Anthracite coal (Carbon)
Pink Garnet in Matrix
Grossular or Almandine Garnet (X3Y2(SiO4)3)
Diamond (Faceted Colorless)
Diamond (Pure Carbon, C)
Quartzite
Quartzite (composed primarily of Silica, SiO2)
Quartzite pebble
Quartzite (SiO2)
Orange Calcite
Calcite (CaCO3)
Quartz (River Pebble)
Silicon Dioxide (SiO2)
Andesite Porphyry (Geological Drill Core)
Andesite Porphyry
Agate
Silicon Dioxide (SiO2)
Orange Calcite
Calcium Carbonate (CaCO3)
Yellow Quartz / Quartz Pebble
Silicon Dioxide (SiO2)
Chalcedony (Agate)
Cryptocrystalline Quartz (SiO2)
Quartz Geode Fragment
Silicon Dioxide (SiO2)
Quartzite Pebble
Quartzite (mostly SiO2)
Agate (Slab)
Agate (Cryptocrystalline variety of Quartz, SiO2)
Ruby
Corundum (Al2O3 with Chromium traces)
Diamond
C (Carbon)
Native Copper Nugget
Native Copper (Cu)
Corundum (Ruby variety)
Aluminium oxide (Al2O3)
Fluorite (left), Sodalite (middle), Dumortierite/Tumbled Quartzite (right)
Calcium Fluoride (CaF2), Sodium Aluminum Silicate Chloride (Na8(Al6Si6O24)Cl2), Aluminum Borosilicate (Al7(BO3)(SiO4)3O3)
Blue Star Sapphire
Corundum (Al2O3)
Ferruginous Sandstone
Arenite with Iron-Oxide Cement (SiO2 with Fe2O3/FeO(OH))
Aragonite (Sputnik habit)
Aragonite (Calcium Carbonate, CaCO3)
Orange Calcite
Calcite (Calcium Carbonate, CaCO3)
Yellow Ochre / Limonite
Limonite (Hydrated Iron(III) Oxide-Hydroxide, FeO(OH)·nH2O)
Kunzite (Pink Spodumene)
Spodumene, LiAl(SiO3)2
Olivine (in Peridotite/Dunite form)
Magnesium Iron Silicate (Mg,Fe)2SiO4
Chert and Chalcedony
Cryptocrystalline Quartz (SiO2)
Ruby
Corundum (Al2O3 with Chromium traces)
Fluorite (likely Fluorite on Quartz/Matrix)
Calcium Fluoride (CaF2)
White Topaz
Al2SiO4(F,OH)2 (Aluminium Silicate Fluoride Hydroxide)
Pink Satin Spar (Satin Spar Selenite Dyed)
Gypsum (CaSO4·2H2O)
Rose Quartz
Silicon Dioxide (SiO2) with trace amounts of titanium, iron, or manganese
Silver (Native Silver/Alloy Specimen)
Ag (Native Silver element), specifically a 90% Ag / 10% Cu alloy
Schist
Mica Schist
Hand-Drawn Trading Card (Amateur Artwork)
Cellulose-based substrate with wax/graphite/ink deposit (n/a for minerals)
Fuchsite
K(Al,Cr)2(AlSi3O10)(OH)2 (Chromium-rich Muscovite)
Magnetite (potentially Hematite-rich)
Magnetite (Fe3O4)
Quartz Geode
Silicon dioxide (SiO2)