Quartz in Host Rock
Silicon Dioxide (SiO2) in Rhyolite or Granite matrix
igneous
Category
Organic Gemstone (Not A Rock)
Browse organic gemstone (not a rock) specimens identified by the Rock Identifier community.
Almandine Garnet in Schist
Almandine Garnet (Fe3Al2(SiO4)3) in Mica Schist
metamorphic
Quartz / Milky Quartz
Silicon Dioxide (SiO2)
mineral
Jasper and Quartzite Pebble
Silicon Dioxide (SiO2) - Microcrystalline Quartz
sedimentary/metamorphic
Chlorastrolite (Greenstone)
Chlorastrolite (variety of Pumpellyite) - Ca2(Mg,Fe)Al2(SiO4)(Si2O7)(OH)2 · H2O
mineral
Rough Agate/Chert Nodules
Cryptocrystalline Quartz (SiO2)
sedimentary
Fire Opal (Common/Precious in Matrix)
Hydrated Silica (SiO2·nH2O)
mineral
Clear Quartz (Carved Dragon)
Quartz (Silicon Dioxide, SiO2)
mineral
Garnet (Almandine)
Almandine, Fe3Al2(SiO4)3
metamorphic
Carnelian Agate
Silicon Dioxide (SiO2) with iron oxide impurities
mineral
Ruby in Zoisite (Anyolite)
Corundum var. Ruby in Zoisite (Al2O3 + (Ca2Al3(SiO4)3(OH)))
metamorphic
Rough Emerald in Matrix
Beryl (Be3Al2Si6O18) with trace Chromium/Vanadium
mineral
Chert (Yellow or Ochre Jasper variant)
Microcrystalline Quartz (SiO2)
sedimentary
Milky Quartz
Silicon Dioxide (SiO2)
mineral
Dendritic Agate
Silicon Dioxide with Manganese/Iron oxide inclusions (SiO2)
Mineral
Red Jasper (Chert)
Silicon Dioxide (SiO2)
sedimentary
Dalmatian Jasper (Dalmatian Stone)
Perthitic feldspar with Arfvedsonite inclusions
igneous
Turquoise
CuAl6(PO4)4(OH)8·4H2O (Hydrous phosphate of copper and aluminium)
mineral
Mixed Tumbled Gemstones and River Rocks
Mixed Decorative Stones (predominantly Silicon Dioxide - SiO2 variants)
Mixed (Igneous, Sedimentary, Metamorphic, and Minerals)
Red Coral
Corallium rubrum (Calcium Carbonate, CaCO3)
Organic Gemstone (Sedimentary classification)
Smoky Quartz (Tumbled)
Silicon Dioxide (SiO2)
mineral
Smoky Quartz
Silicon Dioxide (SiO2)
mineral
Clear Quartz (Rock Crystal)
Silicon Dioxide (SiO2)
mineral
Charoite
Charoite (Hydrated potassium sodium calcium barium strontium silicate hydroxyfluoride)
metamorphic
Pink Tourmaline (Rubellite)
Elbaite (Tourmaline group) - Na(Li,Al)3Al6(BO3)3Si6O18(OH)4
mineral
Coral (Precious Coral)
Corallium rubrum (Red Coral), Paracorallium japonicum (Momo Coral), Pleurocorallium elatius (Sardinian Coral), various other species within the Corallidae family. Chemically, it's primarily Calcium Carbonate (CaCO 3 ).
Mineral, Organic Gemstone
Amethyst Quartz
Silicon Dioxide (SiO2 with iron impurities)
mineral
Blue Lace Agate (Tumbled)
Silicon Dioxide (SiO2)
mineral
Almandine Garnet
Iron aluminum silicate (Fe3Al2(SiO4)3)
mineral
Amethyst (Quartz)
Amethyst (SiO2 with iron impurities)
mineral
Amethyst
Amethyst (SiO2 with Iron impurities)
mineral
Blue Lace Agate
Silicon Dioxide (SiO2)
mineral
Turquoise
Hydrated phosphate of copper and aluminium (CuAl6(PO4)4(OH)8·4H2O)
mineral
Almandine Garnet in Schist
Almandine, Fe3Al2(SiO4)3
metamorphic
Quartz (specifically Citrine or Yellow Quartzite pebble)
Silicon Dioxide (SiO2)
mineral
Chert (Yellow Jasper variant)
Microcrystalline Quartz (SiO2)
sedimentary
Turquoise
Hydrated phosphate of copper and aluminum (CuAl6(PO4)4(OH)8·4H2O)
mineral
Jasper
Jasper (Silicon Dioxide, SiO2)
sedimentary
Chert (Jasper variation)
Silicon Dioxide (SiO2)
sedimentary
Fire Agate
Silicon Dioxide (SiO2) with layered Iron Oxide (Limonite/Goethite)
mineral
Eclogite garnet in matrix
Eclogite (Garnet-Omphacite rock)
metamorphic
Nuummite
Nuummite (Orthoamphibole rock / Anthophyllite-Gedrite blend)
metamorphic