Quartz
Silicon Dioxide (SiO2)
Category
Browse organic gemstone (not a rock or mineral) specimens identified by the Rock Identifier community.
Quartz
Silicon Dioxide (SiO2)
Quartz
Silicon Dioxide (SiO2)
Blue Agate (Tumbled and Dyed)
Silicon Dioxide (SiO2) with likely organic dyes
Precious Opal in Matrix
Hydrated Silica (SiO2·nH2O)
Amber
Fossilized Tree Resin
Petrified Wood
Silicified Wood (SiO2)
Chrysocolla on Matrix
Hydrated copper silicates ((Cu,Al)2H2Si2O5(OH)4·nH2O)
Rose Quartz
Silicon Dioxide (SiO2) with trace amounts of titanium, iron, or manganese
Amber
Succinite (specifically for Baltic Amber), Formula: C10H16O
Quartz Fragment
Silicon Dioxide (SiO2)
Chert
Chert (SiO2)
Chert / Flint
Chert (Silicon Dioxide, SiO2)
Petrified Wood
Silicified Wood (primarily Quartz/Chalcedony, formula SiO2)
Shale or Siltstone
Sedimentary Clastic Rock (Variable mineral composition including quartz and clay minerals)
Serpentine
Antigorite/Lizardite/Chrysotile group, Mg3Si2O5(OH)4
Green Quartz (Prasiolite)
Silicon Dioxide (SiO2) with trace impurities
Sandstone with Trace Fossils
Quartz Arenite with Bioturbation (Trace Fossils)
Fossil Coral
Phylum Cnidaria / Rugosa or Tabulata
Turquoise
Turquoise (Hydrated phosphate of copper and aluminium) CuAl6(PO4)4(OH)8·4H2O
Amethyst
Silicon Dioxide (SiO2) with iron impurities
Red Breccia Jasper
Silicon Dioxide (SiO2) with iron oxide impurities
Chert (often called Jasper or Flint)
Microcrystalline Silica (SiO2)
Pickled Dragon Eggs (Fictional Interpretation: Purple Agate or Amethyst Geodes)
Silicon Dioxide (SiO2) - Microcrystalline Quartz
Sandstone with Brachiopod Mold Fossil
Sedimentary rock (Sandstone) with indeterminate Brachiopod mold
Chert (Jasper/Flint variety)
Silicon Dioxide (SiO2)
Petrified Wood
Silicified Wood (primarily Chalcedony or Quartz, SiO2)
Carnelian (Orange Chalcedony)
Silicon Dioxide (SiO2)
Amethyst
Silicon Dioxide (SiO2) with iron impurities
Chert (Septarian or Nodular variety)
Microcrystalline Quartz (SiO2)
Amber
Succinite (C10H16O)
Jasper
Silicon Dioxide (SiO2)
Milky Quartz
Quartz (SiO2)
Agate (Crazy Lace or Eye Agate)
Silicon Dioxide (SiO2)
Opal
Hydrated Silica (SiO2·nH2O)
Banded Chert
Microcrystalline Quartz (SiO2)
Amber
Succinates (Organic compound: C10H16O)
Amethyst
Amethyst (Silicon Dioxide, SiO2 with Iron impurities)
Coal (Bituminous Coal)
Caustobiolith / Sedimentary Rock
Petrified Wood
Silicified Wood (SiO2)
Unidentified gray rock/mineral specimen
Indeterminate; possibly quartz-rich rock or a metallic sulfide-bearing specimen
Bloodstone
Chalcedony (Quartz)
Chert (Yellow Jasper)
Microcrystalline Quartz (SiO2)