Banded Gneiss
Gneiss (typically quartz, feldspar, mica, amphibole composition)
metamorphic
Category
Not A Natural Rock
Browse not a natural rock specimens identified by the Rock Identifier community.
Bauxite (Concretionary)
Bauxite (Al(OH)3, AlO(OH))
sedimentary
Citrine
Silicon Dioxide (SiO2)
mineral
Limonite with Trace Fossils
Hydrous Iron Oxide Mixture (FeO(OH)·nH2O)
sedimentary
Chalcedony Geode
Chalcedony (SiO2) within a geode structure
Mineral Geode/Sedimentary or Volcanic related
Smoky Quartz
SiO2 (Silicon Dioxide with aluminum impurities)
mineral
Dyed Pink Agate Slice
Cryptocrystalline variety of Quartz (SiO2)
mineral
Black Pearl (Tahitian-style Cultured Pearl)
Calcium Carbonate (Aragonite) with Conchiolin (CaCO3)
mineral
Garden Quartz (Lodalite)
Silicon Dioxide with various mineral inclusions (SiO2)
mineral
Cullet (Slag Glass)
Amorphous Silica (SiO2) with various metal oxide colorants
mineraloid / anthropogenic
Amber
Succinite (Organic Mineraloid) - C10H16O
mineral
Basalt Cobble
Vesicular Basalt (Mafic Extrusive)
igneous
Granodiorite
Granodiorite
igneous
Metaconglomerate
Metaconglomerate (Quartzite conglomerate)
metamorphic
Aura Quartz (Pink/Rose Aura Quartz)
Silicon Dioxide (SiO2) bonded with Platinum and/or Silver
mineral
Bauxite
Bauxite (Al2O3·nH2O)
sedimentary
Dyed Crackle Quartz
Silicon Dioxide (SiO2) with synthetic dye
mineral
Rainbow Hematite (Titanium Coated)
Iron(III) oxide (Fe2O3) with Titanium/Metal Oxide coating
mineral
Cobalt Glass Slug (Man-made Glass)
Amorphous Silica with Cobalt Oxide (SiO2 + CoO)
mineraloid
Lapis Lazuli (polished cabochon)
Lazurite-rich metamorphic rock (approx. Na6Ca2Al6Si6O24(SO4,S,Cl)2)
metamorphic
Amber
Succinite (C10H16O)
mineral
Limonite (Ironstone)
Hydrated Iron Oxide (FeO(OH)·nH2O)
mineral
Obsidian
Volcanic glass (SiO2 - Silicon Dioxide with impurities)
igneous
Limonite (Iron Ore)
Hydrated Iron(III) Oxide-Hydroxide (FeO(OH)·nH2O)
mineral
Dyed Agate Slice
Silicon Dioxide (SiO2) - variety of Chalcedony
mineral
Green Chalcedony (likely Chrysoprase or dyed Green Agate)
Silicon Dioxide (SiO2) with nickel impurities or chromium/dye
mineral
Green Aventurine
Aventurine Quartz (SiO2 with Fuchsite inclusions)
mineral
Rough Diamond
Diamond (Native Carbon), C
mineral
Ambergris
Ambergris (Coprolite-adjacent/Organic secretion)
mineraloid
Blue Sapphire
Corundum (Al2O3 with trace amounts of iron and titanium)
mineral
Green Aventurine
Silicon Dioxide (SiO2) with Fuchsite inclusions
Mineral (Variety of Quartz)
Tahitian Black Pearl
Biogenic Calcium Carbonate (Aragonite/Conchiolin Mixture), CaCO3
mineral
Diamond
Cubic Carbon (C)
mineral
Green Aventurine
Aventurine Quartz (SiO2 with inclusions of Fuchsite)
metamorphic
Chalcedony (Smoky Quartz or Agate nodule fragment)
Silicon Dioxide (SiO2)
mineral
Green Aventurine
Silicon Dioxide with Fuchsite inclusions (SiO2 + K(Al,Cr)2AlSi3O10(OH)2)
metamorphic
Diamond
Diamond (C)
mineral
Ametrine
Ametrine (SiO2 - Silicon Dioxide with varied iron impurities)
mineral
Green Aventurine
Quartzite (variety Aventurine) with Fuchsite inclusions (K(Al,Cr)2(AlSi3O10)(OH)2)
metamorphic
Opalite
Synthetic Glass (Simulated Opal)
mineral
Yellow Quartz (Citrine or Iron-Stained Quartz)
Silicon Dioxide (SiO2)
mineral
Quartz Pebble (Hag Stone / Adder Stone)
Silicon Dioxide (SiO2)
mineral