Obsidian
Volcanic glass (high silica content based on SiO2)
Category
Browse man made material (anthropogenic 'mineraloid') specimens identified by the Rock Identifier community.
Obsidian
Volcanic glass (high silica content based on SiO2)
Turquoise
Hydrated phosphate of copper and aluminium: CuAl6(PO4)4(OH)8·4H2O
Red Jasper
Silicon Dioxide (SiO2) with Hematite (Fe2O3) inclusions
Sandstone
Arenite
Sandstone (likely Graywacke or Arkosic varieties)
Arenite (composed primarily of SiO2)
Wallboard/Drywall (Gypsum-based)
Gypsum (Calcium Sulfate Dihydrate) - CaSO4·2H2O
Chert (varieties include Flint and Jasper)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Sandstone
Sandstone (composed primarily of sand-sized minerals or rock grains)
Lapis Lazuli
Lapis Lazuli (a rock type, not a single mineral; main component is Lazurite (Na,Ca)8[(S,Cl,SO4,OH)2|(Al6Si6O24)])
Granite
Granite (Felsic Plutonic Rock)
Rose Quartz
Silicon Dioxide (SiO2) with trace amounts of titanium, iron, or manganese
Granite
Phaneritic Plutonic Felsic Rock (SiO2 > 69%)
Limestone (with potential fossil inclusions)
Calcium Carbonate (CaCO3)
Rose Quartz
Quartz (SiO₂), specifically a variety of Quartz
Bauxite Ore
Hydrated aluminum oxides (e.g., Gibbsite Al(OH)3, Boehmite ̲̲̲̲AlOOH, Diaspore ̲̲̲̲AlOOH)
Jasper (Imperial Jasper style)
Silicon Dioxide (SiO2) with impurities
Diamond (set in Gold)
Diamond (pure carbon, C)
Blue Kyanite
Kyanite (Al2SiO5)
Quartz (Milky Quartz)
Silicon Dioxide (SiO2)
Limestone
Calcium Carbonate (CaCO3)
Jasper and Aquamarine (likely)
Jasper (Cryptocrystalline Quartz (SiO2)), Aquamarine (Beryl (Be3Al2Si6O18))
Granite
Granite (a common term for a felsic intrusive igneous rock)
Granite
Felsic Intrusive Igneous Rock
Pyrite (Fool's Gold)
Iron Disulfide (FeS2)
Dendritic Agate (or Dendritic Opal)
SiO2 (for Agate), SiO2·nH2O (for Opal)
Malachite
Malachite (Cu2CO3(OH)2)
Diamond
Diamond (C)
Sandstone (likely Arkosic)
Clastic Sedimentary Rock
Sandstone (Ferruginous)
Arenite (Fe2O3 stained)
Limestone
CaCO3 (Mainly Calcite or Aragonite)
Limestone (Micrite/Chalky variety)
Calcium Carbonate (CaCO3)
Rose Quartz
Silicon Dioxide (SiO2) with trace amounts of titanium, iron, or manganese
Rose Quartz
Silicon Dioxide (SiO2) with trace amounts of titanium, iron, or manganese
Oak-grain Laminate (Industrial/Decorative Furniture Finish)
Melamine Resin-impregnated Decorative Paper on Particleboard (Cellulose/Thermosetting Plastic)
Quartz (likely) or a Quartzite Pebble
Silicon dioxide (SiO2) for quartz. If it's quartzite, it's a metamorphic rock primarily composed of quartz.
Rose Quartz
Silicon Dioxide (SiO2) with trace amounts of titanium, iron, or manganese
Rose Quartz
Silicon dioxide (SiO2) with trace amounts of titanium, iron, or manganese
River Pebble (Likely Chert or Fine-Grained Sandstone/Quartzite)
Siliciclastic clast (likely Chert or Quartzarenite/Quartzite pebble)
Pink Granite (Fragment)
Pink Granite (dominated by Potassium Feldspar: KAlSi3O8)
Milky Quartz
Silicon dioxide (SiO2)
Granite
Granite (Felsic Plutonic Rock)
Specular Hematite (Iron Ore)
Iron(III) oxide (Fe2O3)