Amethyst (Variety of Quartz)
Silicon Dioxide (SiO2) with iron impurities
Category
Browse granite specimens identified by the Rock Identifier community.
Amethyst (Variety of Quartz)
Silicon Dioxide (SiO2) with iron impurities
Chevron Amethyst
Silicon Dioxide (SiO2) with trace Iron (Fe4+)
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
Amethyst
Amethyst (Silicon Dioxide, SiO2 with Iron impurities)
Clear Quartz Fragment
Quartz (Silicon Dioxide, SiO2)
Gold Nugget
Native Gold (Au)
Tiger's Eye
Tiger's Eye (Pseudomorph of Quartz after Crocidolite), SiO2
Chert Nodule
Microcrystalline Quartz (SiO2)
Limonite (Iron Ore)
Hydrous ferric oxides (FeO(OH)·nH2O)
Milky Quartz
Silicon Dioxide (SiO2)
Common Opal with Host Rock
Opal (Hydrated silica, SiO2·nH2O)
Fuchsite
Chrome-bearing Muscovite [K(Al,Cr)2(AlSi3O10)(OH)2]
Blue Chalcedony (likely dyed)
Silicon Dioxide (SiO2) - Cryptocrystalline Quartz
Quartzite
Quartzite (SiO2)
Gold Flakes
Native Gold (Au)
Dyed Aura Quartz
Silicon Dioxide (SiO2) with metallic coating
Lapis Lazuli (Low-grade/Calcite-heavy)
Na8[Al6Si6O24]n(S,Cl,SO4,OH)2 (Lazurite component)
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
Milky Quartz
Silicon Dioxide (SiO2)
Quartz Pebble (Chert/Chalcedony variety)
Silicon Dioxide (SiO2)
Chert (Jasper/Agate variety)
Microcrystalline Quartz (SiO2)
Chert (Nodule)
Microcrystalline or cryptocrystalline Quartz (SiO2)
Quartzite
Quartzite (SiO2)
Pyrite (Iron Pyrites)
Iron Sulfide (FeS2)
Limonite (Iron Ore)
Hydrated Iron(III) Oxide-Hydroxide (FeO(OH)·nH2O)
Quartz (Milky Quartz)
Silicon Dioxide (SiO2)
Basalt
Basalt
Chalcedony
Cryptocrystalline Quartz (SiO2)
Dyed Agate
Silicon Dioxide (SiO2) with synthetic dyes
Limonite (Iron Ore Congcretion)
Limonite (a mixture of hydrated iron(III) oxide-hydroxides, FeO(OH)·nH2O)
Quartz Pebble
Quartz (Silicon Dioxide, SiO2)
Tiger's Eye
Pseudomorph of Quartz after Crocidolite (SiO2 with inclusions of Iron Oxide)
Ametrine
Ametrine (SiO2 - Silicon Dioxide with varied iron impurities)
Moonstone (in a halo ring setting)
Orthoclase Feldspar (containing alternating layers of Albite), (KAlSi3O8)
Quartzite (River Pebble)
SiO2 (recrystallized Quartz)
Rough Emerald
Emerald (Beryl), Be3Al2(SiO3)6
Quartzite
Quartzite (primarily SiO2)
Bornite (Peacock Ore)
Bornite (Cu5FeS4)
Milky Quartz
Silicon Dioxide (SiO2)
Zoisite with Ruby
Anyolite (Calcium aluminum hydroxy silicate with Corundum) Ca2Al3(SiO4)3(OH)
Silicon Carbide (Carborundum)
Moissanite (SiC), though mostly synthetic
Diamond
Diamond (pure Carbon, C)