Amethyst (Purple), Sulfur (Yellow), and Blue Apatite
SiO2 (Quartz), S (Native Sulfur), Ca5(PO4)3(F,Cl,OH) (Apatite Group)
Category
Browse industrial byproduct (often mistaken for obsidian or mineral) specimens identified by the Rock Identifier community.
Amethyst (Purple), Sulfur (Yellow), and Blue Apatite
SiO2 (Quartz), S (Native Sulfur), Ca5(PO4)3(F,Cl,OH) (Apatite Group)
Greywacke
Greywacke (Lithofeldspathic Sandstone)
Chert (often called Flint or Jasper)
Silicon Dioxide (SiO2)
Synthetic Resin Charm (Seal Shape)
Polymer Resin with plastic glitter / Polyethylene terephthalate glitters
Chert (Nodule)
Silicon Dioxide (SiO2)
Limestone
Calcium Carbonate (CaCO3)
Quartzite
Quartzite (SiO2)
Chert (specifically Gray/Blue-Gray Chert)
Chert (SiO2)
Quartz Pebble
Silicon Dioxide (SiO2)
Blue Sapphire
Corundum (Al2O3) with traces of Iron and Titanium
Basalt
Basalt
Quartzite
Quartzite (primarily SiO2)
Quartzite
Quartzite (SiO2)
Beach Quartzite (Yellow-stained Quartz)
Quartzite (SiO2 with Iron oxide staining)
Chert (Gravel pebble)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Clear Quartz (Rock Crystal)
Quartz (Silicon Dioxide - SiO2)
Sandstone (Pebble)
Arenite (primarily SiO2)
Chert (Nodule)
Silicon dioxide (SiO2) - Cryptocrystalline Quartz
Granite (Pegmatitic)
Phaneritic Felsic Igneous Rock
Quartzite (Water-worn Pebble)
Metamorphosed Quartz Sandstone (SiO2)
Quartzite (Iron-stained)
Metamorphosed Quartz-rich Rock (SiO2)
Quartzite
Quartzite (primarily SiO2)
Quartzite
Quartzite (SiO2)
Schist
Mica Schist
Garnet Rhyolite
Rhyolite (high-silica volcanic rock) with almandine/spessartine garnet
Quartz Vein in Host Rock (clastic sediment)
Silicon Dioxide (SiO2) in matrix
Anthracite
Anthracite (Carbon-rich metamorphic coal)
Quartzite (River Cobble)
Quartzite (Metamorphosed Quartz Sandstone, SiO2)
Quartz Pebble (Water-Worn)
Silicon Dioxide (SiO2)
Peridot
Olivine (Magnesium Iron Silicate - (Mg, Fe)2SiO4)
Peridot (Olivine)
Olivine, (Mg, Fe)2SiO4
Diamond (appearing in jewelry)
Diamond (pure Carbon, C)
Aqua Aura Quartz
Titanium/Gold-coated Silicon Dioxide (SiO2)
Black Tourmaline
Schorl (NaFe3Al6(BO3)3Si6O18(OH)4)
White Quartz (Milky Quartz)
Silicon Dioxide (SiO2)
Cubic Zirconia (CZ) in Gold-Plated Setting
Cubic Zirconium Dioxide (ZrO2)
Gold Nugget
Native Gold (Au)
Chert Nodule (Flint)
Microcrystalline Quartz (SiO2)
Rough Quartz
Silicon Dioxide (SiO2)
Serpentinite
Serpentinite (composed primarily of Serpentine group minerals, (Mg,Fe,Ni,Al,Zn,Mn)2-3(Si,Al,Fe)2O5(OH)4)
Basalt
Basalt (Aphanitic Mafic Igneous Rock)
Muscovite Mica (in Quartz matrix)
Potassium aluminum silicate hydroxide fluoride (KAl2(AlSi3O10)(F,OH)2)