Amethyst
SiO2 (Amethyst is a variety of Quartz)
Category
Browse crystal specimens identified by the Rock Identifier community.
Amethyst
SiO2 (Amethyst is a variety of Quartz)
Amethyst Quartz (Chevron Amethyst)
Silicon Dioxide (SiO2) with iron impurities
Chevron Amethyst
SiO2 (Quartz with Manganese/Iron impurities)
Quartz (specifically Clear Quartz or Rock Crystal)
Silicon Dioxide (SiO2)
Honey Calcite Geode Segment
Calcite (Calcium Carbonate, CaCO3)
Garnet (specifically Almandine or Pyrope)
Almandine: Fe3Al2(SiO4)3 or Pyrope: Mg3Al2(SiO4)3
Quartz Druzy Geode
Silicon Dioxide (SiO2) - Crystalline Variety
Eudialyte in Matrix
Eudialyte [Na15Ca6(Fe,Mn)3Zr3(Si25O73)(O,OH,H2O)3(Cl,OH)2]
Porphyry
Porphyritic Igneous Rock (likely Porphyritic Andesite or Basalt)
Smoky Quartz
Silicon Dioxide (SiO2)
Pegmatite (with smoky quartz and tourmaline/biotite)
Pegmatitic Granite
Amethyst
Silicon Dioxide (SiO2) with iron impurities
Goldstone (Red)
Aventurine Glass (SiO2 + Cu)
Geodal Limestone / Calcite Druze
Calcium Carbonate (CaCO3)
Garnet Schist
Almandine Garnet Schist (Fe3Al2(SiO4)3 in Schistose matrix)
Blue Cracked Quartz (Dyed Fire Crackle Quartz)
Silicon Dioxide (SiO2) with synthetic dye
Ferruginous Quartz (Iron-stained Quartz)
Silicon Dioxide (SiO2) with Hematite/Limonite inclusions
Rutilated Quartz (with Garnet pendant)
Silicon Dioxide (SiO2) with Titanium Dioxide (TiO2) inclusions
Aura Quartz Geodes (Lab-Altered)
Silicon Dioxide (SiO2) with Metallic Vapor Deposition
Red Tiger's Eye
Silicified Crocidolite (Quartz pseudo-morph after Crocidolite), SiO2
Amethyst (Quartz)
Silicon Dioxide (SiO2) with Iron impurities
Quartz Druzy on Matrix (likely Agate or Jasper)
Silicon Dioxide (SiO2) with various mineral inclusions
Almandine Garnet
Almandine (Fe3Al2Si3O12)
Basalt with Quartz/Zeolite Inclusions
Porphyritic Basalt (SiO2 with Aluminosilicates)
Pyrite (on host rock/ore)
Iron Sulfide (FeS2)
Amethyst/Smoky Quartz Cluster
Silicon Dioxide (SiO2)
Clear Quartz
Silicon Dioxide (SiO2)
Green Tourmaline
Elbaite (part of Tourmaline group), Na(Li1.5Al1.5)Al6Si6O18(BO3)3(OH)4
Emerald in Matrix
Beryl (Be3Al2Si6O18) containing Chromium/Vanadium impurities
Herkimer Diamond
Quartz (Silicon Dioxide, SiO2)
Granite
Granite (Silicic Intrusive Igneous Rock)
Granite (Pink/Red Orthoclase variety)
Phaneritic Plutonic Felsic Rock (SiO2, KAlSi3O8, NaAlSi3O8, CaAl2Si2O8)
Amethyst
Silicon Dioxide (SiO2) with iron impurities
Pyrite
Iron Sulfide (FeS2)
Quartz Geode
Silicon Dioxide (SiO2)
Tourmalinated Quartz
Quartz (SiO2) with included Tourmaline (complex borosilicate)
Marble
Recrystallized Limestone (CaCO3)
Quartz Druzy on Matrix (with Copper Mineralization)
Silicon Dioxide (SiO2) with Chrysocolla (Cu2-xAlx(H2-xSi2O5)(OH)4·n H2O)
Dearest Jewelry (Multigemstone)
Combination of Diamond (C), Emerald (Be3Al2Si6O18), Amethyst/Rock Crystal (SiO2), Ruby (Al2O3), Emerald (Be3Al2Si6O18), Sapphire (Al2O3), and Topaz (Al2SiO4(F,OH)2)
Granite (with Beryl/Aquamarine)
Granite (Feldspar, Quartz, Mica, and Beryl Be3Al2Si6O18)
Pink Granite
Phaneritic Felsic Igneous Rock (Granite)
Coarse-grained Granite (Quartz and Feldspar dominated)
Granitoid (KAlSi3O8 – NaAlSi3O3 – CaAl2Si2O8 – SiO2)