Purple Agate (Dyed Chalcedony)
SiO2 (Silicon Dioxide) with organic dyes
Category
Browse organic gemstone (sedimentary classification) specimens identified by the Rock Identifier community.
Purple Agate (Dyed Chalcedony)
SiO2 (Silicon Dioxide) with organic dyes
Shungite (Noble/Type II)
Non-crystalline carbon (Fullerene-bearing carbonaceous rock)
Turquoise
Hydrated phosphate of copper and aluminium: CuAl6(PO4)4(OH)8·4H2O
Opal (Precious Opal)
Hydrated Silica (SiO2·nH2O)
Agate (Grey Agate Slice)
Microcrystalline Quartz (SiO2)
Rhodochrosite
Manganese carbonate (MnCO3)
Blue Kyanite
Kyanite (Al2SiO5)
Tiger's Eye and Carnelian Quartz
Silicon Dioxide (SiO2)
Chert (Grey Flint)
Silicon Dioxide (SiO2) - Microcrystalline Quartz
Amber
Succinite (C10H16O)
Ambergris
Ambergris (Coprolite-adjacent/Organic secretion)
Chert (Jasper variety)
Silicon Dioxide (SiO2)
Banded Agate (with possible Chalcedony layers)
Silicon dioxide (SiO2)
Yellow Calcite
Calcium Carbonate (CaCO3)
Quartz / Rock Crystal
Silicon Dioxide (SiO2)
Amber
Succinite (fossilized resin); C10H16O
Chert (Jasper/Flint variation)
Chert (SiO2)
Yellow Jasper
Silicon Dioxide (SiO2) with goethite or iron oxide inclusions
Yellow Jasper
Silicon Dioxide with Iron inclusions (SiO2)
Chert (specifically Flint)
Microcrystalline or cryptocrystalline Quartz (SiO2)
Conglomerate
Conglomerate
Amber
Succinite (a specific common type) or Fossilized Tree Resin (C10H16O)
Milky Quartz
Silicon Dioxide (SiO2)
Jasper River Pebble
Silicon Dioxide (SiO2)
Magnetite
Magnetite (Iron(II,III) oxide, Fe3O4)
Shungite
Non-crystalline carbon (Fullerenes / Carbon-60)
Aragonite (Star Cluster or Twinned variety)
Aragonite (Calcium Carbonate, CaCO3)
Tree Agate
Dendritic Agate (Silicon Dioxide, SiO2)
Amber
Succinite
Amber
Succinite (specifically for Baltic amber); Complex mixture of organic compounds (C10H16O)
Moss Agate
Silicon Dioxide (SiO2) with inclusions of manganese or iron oxides
Quartz (likely) or a Quartzite Pebble
Silicon dioxide (SiO2) for quartz. If it's quartzite, it's a metamorphic rock primarily composed of quartz.
Garnet Schist
Garnetiferous Micaceous Schist
Garnet (Almandine/Pyrope variety)
Silicate mineral group; typically Fe3Al2(SiO4)3 (Almandine) or Mg3Al2(SiO4)3 (Pyrope)
Clear Quartz (Rock Crystal)
Silicon Dioxide (SiO2)
Rough Quartz
Quartz (Silicon Dioxide, SiO2)
Red Jasper
Jasper (Silicon Dioxide with Iron Oxide inclusions, SiO2)
Carnelian
Carnelian (a variety of Chalcedony, SiO ₂)
Moss Agate
Silicon Dioxide (SiO2) with inclusions of manganese or iron oxide
Amber
Succinite (specifically Baltic Amber) - Formula: C10H16O (approximate)
Amber
Succinite (C10H16O)
Anthracite Coal
Anthracite (Carbon-based metamorphic rock, 86-97% C)