Sandstone
Arenite (primarily SiO2)
Category
Browse organic (paper and cellulose) specimens identified by the Rock Identifier community.
Sandstone
Arenite (primarily SiO2)
Paraiba Tourmaline
Elbaite Tourmaline (Na(Li,Al)3Al6(BO3)3Si6O18(OH)4) - Copper-bearing
Pyromorphite on Epidote
Pyromorphite [Pb5(PO4)3Cl] and Epidote [Ca2(Al2,Fe3+)(SiO4)3(OH)]
Fairy Stone (Staurolite)
Staurolite (Fe2+2Al9Si4O22(OH)2)
Milky Quartz
Silicon Dioxide (SiO2)
Sandstone (Pebble)
Arenite (primarily SiO2)
Green Quartz (Prasiolite/Adventurine)
Silicon Dioxide (SiO2) with inclusions
Chert (Jasper variation)
Microcrystalline Quartz (SiO2)
Milky Quartz Pebble
Crystalline Silicon Dioxide (SiO2)
Banded Quartzite River Pebble
Metamorphosed Quartz-rich Sandstone (SiO2)
White Quartz (Milky Quartz)
Silicon Dioxide (SiO2)
Chert (or Flint)
Microcrystalline or cryptocrystalline Quartz (SiO2)
Fluorite (Green)
Fluorite (Calcium Fluoride, CaF2)
Orange Calcite
Calcium Carbonate (CaCO3)
Milky Quartz Pebble
Quartz (Silicon Dioxide, SiO2)
Blue Apatite
Apatite - Ca5(PO4)3(F,Cl,OH)
Quartz Geode (Cracked)
Quartz (Silicon Dioxide, SiO2)
Sandstone (Ferruginous)
Arenite (complex silicate composition with iron oxides)
Sandstone
Arenite (SiO2 primarily)
Quartz pebble (Quartztite fragment)
Silicon Dioxide (SiO2)
Yellow Agate
Silicon Dioxide (SiO2)
Quartzite with Quartz Vein
Metamorphosed sandstone (SiO2)
Yellow Quartz Pebble
Silicon Dioxide (SiO2)
Red Granite
Felsic Intrusive Igneous Rock
Calcite on Limestone (or Fossil)
Calcium Carbonate (CaCO3)
Larimar
Pectolite, NaCa2Si3O8(OH)
Amethyst (Polished/Carved Crystal)
Silicon Dioxide (SiO2) with trace Iron (Fe)
Chert
Chert (SiO2)
Fossiliferous Limestone with Brachiopod
Phylum Brachiopoda in calcitic matrix
Synthetic Convention Badge (Plastic/PVC)
Polyvinyl Chloride (PVC) / Polycarbonate
Quartz (Milky/Crystalline variety)
Silicon Dioxide (SiO2)
Coal
Bituminous or Anthracite coal (carbon-rich sedimentary rock)
Sandstone (likely Siltstone)
Arenite or Siltstone (high SiO2 content)
Raw Green Aventurine
Aventurine Quartz (SiO2 + Fuchsite)
Pyrite (Fool's Gold)
Iron Sulfide (FeS2)
Blue Quartz (Aventurine)
Silicon Dioxide (SiO2) with inclusions of crocidolite or dumortierite
Rose Quartz
SiO2 (Silicon Dioxide)
Dalmatian Jasper
Peralkaline rhyolite with Arfvedsonite inclusions
Quartzite
Quartzite (SiO2)
Chert (Flint)
Silicon Dioxide (SiO2)
Sandstone
Arenite (primarily SiO2)
Diamond Plate (Steel)
Alloyed Carbon Steel or Aluminum with 'Durbar' pattern