Chert (Iron-stained)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Category
Browse organic gemstone (not a rock or mineral) specimens identified by the Rock Identifier community.
Chert (Iron-stained)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Black Tourmaline
Schorl (Na(Fe²⁺)₃Al₆(BO₃)₃Si₆O₁₈(OH)₄)
Yellow Quartz (Citrine Quartz or Yellow Jasper)
Silicon Dioxide (SiO2) with iron impurities
Clear Quartz
Quartz (Silicon Dioxide, SiO2)
Chert (Yellow Jasper)
Microcrystalline Quartz (SiO2)
Greenstone (Epidote/Chlorite-rich Metabasalt)
Greenschist / Epidosite (Ca2(Al,Fe)3(SiO4)3(OH))
Opal
Hydrated Silica (SiO2·nH2O)
Chert (often called Flint or Jasper)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Smoky Quartz
Silicon Dioxide (SiO2)
Massive Quartz
Silicon Dioxide (SiO2)
Chert (Chalcedony/Jasper)
Microcrystalline Quartz (SiO2)
Amethyst Quartz (Tumbled)
Amethyst (Silicon Dioxide with iron impurities, SiO2)
Unakite
Epidotized Granite
Agate (Grey Agate Slice)
Microcrystalline Quartz (SiO2)
Carnelian
Carnelian (a variety of Chalcedony, SiO₂)
Quartz (specifically Clear Quartz or Rock Crystal)
Silicon Dioxide (SiO2)
Garnet-Bearing Schist
Almandine Garnet Micaceous Schist
Jasper (specifically Yellow Jasper and Red Jasper)
Silicon Dioxide (SiO2) with iron oxide inclusions
Petrified Wood
Silicified Wood (SiO2)
Jasper (specifically a banded or dark variety)
Silicon Dioxide (SiO2) with impurities
Clear Quartz (Rock Crystal)
Quartz (Silicon Dioxide, SiO2)
Banded Chert
Microcrystalline silicon dioxide (SiO2)
Quartz (Milky and Bull Quartz)
Silicon Dioxide (SiO2)
Almandine Garnet
Almandine (Fe3Al2Si3O12)
Picasso Jasper (or Picasso Marble)
Metamorphosed Limestone (Calcium Carbonate, CaCO3, with impurities)
Quartz (specifically Clear Quartz with iron/hematite staining)
Silicon Dioxide (SiO2)
Yellow Jasper (Iron-stained Chert)
Silicon Dioxide (SiO2) with iron oxide (Limonite/Goethite) inclusions
Chert / Flint
Cryptocrystalline Quartz (SiO2)
Quartz (Specifically Clear to Smoky Quartz point)
Silicon Dioxide (SiO2)
Pyrite
Iron Sulfide (FeS2)
Chert (Jasper/Chalcedony)
Microcrystalline Silica (SiO2)
Coquina Limestone (Fossiliferous Limestone)
Calcareous bioclastic sedimentary rock (CaCO3)
Limestone (specifically Fossiliferous or Crinoidal Limestone)
Calcium Carbonate (CaCO3) - Calcite Rock
Quartz (Rose or Clear variety)
Silicon Dioxide (SiO2)
Diamond
Diamond (pure Carbon, C)
Red Jasper
Jasper (Silicon Dioxide, SiO2)
Banded Chert (River Siltstone)
Microcrystalline Quartz (SiO2)
Pyrite
Iron Sulfide (FeS2)
Amygdaloidal Basalt
Amygdaloidal Basalt (Mafic volcanic rock with secondary mineral fillings)
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
Pyrite (Fool's Gold) Cube
Iron Sulfide (FeS2)
Chert (Jasper/Flint variant)
Silicon Dioxide (SiO2)