Organic Materia (Not A Rock Or Mineral)

Sandstone

Arenite (Siliclastic sedimentary rock)

Drill Core Sample

Cylindrical Rock Core (Specific mineralogy varies by extraction site)

Sandstone (Quartzose Sandstone)

Clastic sedimentary rock (SiO2 major component)

Granite

Phaneritic Plutonic Felsic Rock

Chert (and Flint)

Silicon dioxide (SiO2) - Microcrystalline quartz

Milky Quartz

Silicon Dioxide (SiO2)

Gneiss

Gneissic Metamorphic Rock

Diamond in Kimberlite

Kimberlite host rock with C (Carbon) inclusion

Turquoise

Hydrous phosphate of copper and aluminium [CuAl6(PO4)4(OH)8·4H2O]

Sandstone

Arenite (SiO2 based)

Sandstone (Fossiliferous)

Arenite / Clastic Sedimentary Rock

Concrete Fragment

Hardened Portland Cement Composite

Muscovite Mica

Muscovite - KAl2(AlSi3O10)(F,OH)2

Greenstone

Greenschist (metamorphosed mafic igneous rock)

Wishing Stone (Quartz-veined Siltstone or Graywacke)

Hydrothermal Quartz vein in matrix of SiO2 (Quartz) and Al2O3 (Clay minerals)

Granite

Phaneritic Felsic Igneous Rock

Granite

Phaneritic intrusive igneous rock

Amethyst

Crystalline Quartz (SiO2) with iron impurities

Gold Nugget

Native Gold (Au)

Concretion (Sandstone)

Carbonate-cemented Sandstone Concretion

Turquoise

Turquoise (CuAl6(PO4)4(OH)8·4H2O)

Granite (with Quartz and Mica)

Phaneritic Felsic Igneous Rock

Turquoise

Hydrated phosphate of copper and aluminium - CuAl6(PO4)4(OH)8·4H2O

Shale with Iron Oxide Staining

Fissile Mudstone (primarily clay minerals and quartz)

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

Peridot (Olivine)

(Mg,Fe)2SiO4 (Magnesium Iron Silicate)

Banded Gneiss

Gneiss (High-grade Regional Metamorphic Rock)

Clear Quartz (Rock Crystal)

Silicon Dioxide (SiO2)

Clear Quartz (Rock Crystal)

Silicon Dioxide (SiO2)

Quartz (Druzy or Crystalline variety)

Silicon Dioxide (SiO2)

Clear Quartz crystals on a Matrix base (Geode fragment)

Silicon Dioxide (SiO2)

Ferruginous Sandstone (Red Sandstone)

Arenite with Hematite/Limonite cement

Stiped Slate Beach Pebble

Low-grade Metamorphic Slate with Quartz Vein (SiO2 on Phyllosilicate base)

River Jasper (Chert/Chalcedony mix)

Silicon Dioxide (SiO2) with iron oxide and chlorite inclusions

Amethyst Geode

Amethyst (Silicon Dioxide), Formula: SiO2

Chert (Dark Variety / Flint)

Silicon Dioxide (SiO2)

Banded Chert

Microcrystalline Quartz (SiO2)

Chert (Jasper variety)

Silicon Dioxide (SiO2)

Chert (Cherty Flint)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Chert (varieties include Flint and Jasper)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Chert (variant Flint)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Chert (Flint)

Chert (Microcrystalline Quartz, SiO2)