Moonstone (bead form)
Potassium Aluminum Silicate (KAlSi3O8) - a variety of Orthoclase Feldspar
Mineral
Category
Man Made (Synthetic Rock)
Browse man made (synthetic rock) specimens identified by the Rock Identifier community.
Amethyst
SiO2 (Silicon Dioxide)
Mineral
Ruby
Corundum (Aluminium Oxide with Chromium impurities, Al2O3:Cr)
mineral
Ruby (Corundum)
Corundum (Aluminum Oxide) with chromium trace elements, Al2O3
mineral
Diamond (Cut jewelry specimen)
Diamond (pure Carbon, C)
mineral
Ruby in Matrix
Corundum (Al2O3)
mineral
Chert (specifically Flint Arrowhead)
Silicon dioxide (SiO2) - Microcrystalline Quartz
sedimentary
Rose Quartz
Silicon Dioxide (SiO2)
mineral
Hematite
Iron(III) oxide (Fe2O3)
mineral
Hematite
Iron(III) oxide (Fe2O3)
mineral
Sapphire (likely blue synthetic sapphire or blue glass in a ring)
Corundum (Al₂O₃), specifically the blue variety due to trace amounts of iron and titanium impurities. If synthetic, it would still be Al₂O₃.
Mineral
Obsidian
Obsidian (volcanic glass, amorphous silica rich rock)
Igneous
Blue Goldstone
Aventurine Glass (SiO2 with Co and metallic inclusions)
mineral (synthetic glass)
Fossiliferous Limestone
Limestone (composed primarily of calcite with included fossils CaCO3)
Sedimentary
Staurolite (Cross Stone)
Staurolite (Fe2+2Al9Si4O23(OH))
metamorphic
Smoky Quartz
SiO2 (Silicon Dioxide)
mineral
Rose Quartz
Silicon Dioxide (SiO2) with trace amounts of titanium, iron, or manganese
mineral
Chert (specifically Yellow/Brown Chert or Flint)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
sedimentary
Jadeite and Mixed Gemstones (Ruby, Sapphire, Emerald)
Jadeite (NaAlSi2O6), Corundum (Al2O3), Beryl (Be3Al2(Si6O18))
mineral
Obsidian
Volcanic Glass (70% or more SiO2)
igneous
Blue Opal Inlay (Simulated/Lab-created)
Hydrated Amorphous Silica (SiO2·nH2O) with polymer resin
mineraloid
Diamond Plate (Steel)
Alloyed Carbon Steel or Aluminum with 'Durbar' pattern
not a rock (Man-made industrial metal)
Bismuth
Bismuth (Bi)
Mineral
Prehnite
Prehnite, Ca2Al2Si3O10(OH)2
Mineral
Obsidian
Volcanic glass (SiO2 - Silicon Dioxide)
igneous
Chert
Chert (microcrystalline quartz)
sedimentary
Engineered Quartz Stone
Agglomerated Quartz (SiO2 + Polymer Resin)
mineral-based composite
Diamond
Diamond (pure Carbon, C)
mineral
Ruby
Corundum (mineral species), variety: Ruby (Al2O3 with Cr3+ as the chromophore)
Mineral
Emerald
Beryl (Be3Al2(SiO3)6) with Chromium/Vanadium impurities
mineral
Sandstone
Arenite
sedimentary
Coquina
Bioclastic Limestone
sedimentary
US Penny
Cuprum (Copper: Cu) and Zincum (Zinc: Zn) Alloy
Man-made object (metal alloy)
Diamond
Native Carbon (C)
mineral
Asphalt Concrete
Bituminous Concrete / Asphaltic Composite
not a natural rock (man-made composite)
Limonite (Iron Ore)
Hydrous Iron Oxide (goethite, lepidocrocite)
Mineral
Cubic Zirconia (Simulated Diamond)
Zirconium Dioxide (ZrO2)
mineral (synthetic)
Smoky Quartz
Silicon Dioxide (SiO2)
mineral
Diamond
Cubic carbon (C)
mineral
Quartz
Silicon dioxide (SiO₂)
Mineral
Marble
Marble (metamorphosed limestone or dolostone), primarily composed of calcite (CaCO3) or dolomite (CaMg(CO3)2)
metamorphic
Rough Corundum (likely Sapphire or Common Corundum)
Aluminum oxide (Al2O3)
mineral