Blue gemstone in a decorative setting (possibly blue spinel or sapphire)
Unidentified blue faceted gemstone; sapphire is corundum (Al₂O₃), while spinel is MgAl₂O₄
gemstone
Category
Metamorphic And Igneous Rocks
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Yellow Sapphire
Corundum (Al2O3)
gemstone
Dalmatian Jasper
Microcrystalline Quartz with Tourmaline or Arfvedsonite inclusions
igneous
Chalcopyrite
CuFeS2 (Copper Iron Sulfide)
mineral
Likely milky quartz fragment
Quartz, silicon dioxide (SiO₂)
mineral
Limestone
Calcium Carbonate (CaCO3)
sedimentary
Milky Quartz
Silicon Dioxide (SiO2)
mineral
Muscovite Mica
KAl2(AlSi3O10)(OH)2
mineral
Quartz
Silicon Dioxide (SiO2)
mineral
Quartz with Gold
Silicon Dioxide with Native Gold (SiO2 + Au)
mineral
Limonite
FeO(OH)•nH2O
mineral
Limonite
FeO(OH)•nH2O
mineral
Limonite
FeO(OH)·nH2O
mineral
Ruby
Corundum (Al2O3:Cr)
gemstone
Ruby
Corundum (Al2O3:Cr)
gemstone
Quartz vein in dark host rock
Likely milky quartz in a fine-grained mafic or metamorphic host; exact host identification is uncertain from the image.
metamorphic
Ruby in Quartz
Corundum in Quartz (Al2O3 in SiO2)
gemstone
Calcite (with iron oxide staining)
Calcium Carbonate (CaCO3)
mineral
Stone Mosaic Mask
Composite silicate and carbonate minerals
mineral
Star Ruby
Corundum (Al2O3)
gemstone
Quartz
Silicon Dioxide (SiO2)
mineral
Magnetite (Lodestone variety)
Magnetite (Fe3O4)
mineral
Blue Apatite
Fluorapatite (Ca5(PO4)3F)
mineral
Ruby
Corundum (Al2O3:Cr)
gemstone
Quartz Vein in Host Rock
Silicon Dioxide (SiO2)
mineral
Ruby
Corundum (Al2O3:Cr)
gemstone
Ruby (in a ring setting)
Corundum (Al2O3:Cr)
gemstone
Nephrite Jade
Nephrite
Mineral/Rock
Kunzite
Spodumene (LiAl(SiO3)2)
gemstone
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
mineral
Orange Calcite
Calcium Carbonate (CaCO3)
mineral
Quartz Pebble (Smoky Quartz / Chalcedony)
Silicon Dioxide (SiO2)
mineral
K2 Jasper (K2 Stone)
Azurite in Granite / Quartzite
metamorphic
Yellow Calcite
Calcium Carbonate (CaCO3)
mineral
Rutilated Quartz
Quartz with Rutile inclusions (SiO2 with TiO2)
mineral
Clear Quartz (Faceted)
Silicon dioxide (SiO2)
gemstone
Moonstone
Orthoclase (KAlSi3O8)
mineral
Blue Apatite
Apatite (Group), Ca5(PO4)3(F,Cl,OH)
mineral
Sapphire
Corundum (Al2O3)
mineral
Zoisite with Hornblende
Zoisite (Ca2Al3(SiO4)3(OH)) with Amphibole inclusions
metamorphic
Quartz (Milky/Rose Quartz)
Silicon Dioxide (SiO2)
mineral
Quartz vein in host rock
Milky quartz (SiO₂), likely in a metamorphic host such as schist or gneiss
metamorphic