Chert (often called Flint when found in chalk)
Microcrystalline Quartz (SiO2)
Category
Browse organic gemstone (biogenic) specimens identified by the Rock Identifier community.
Chert (often called Flint when found in chalk)
Microcrystalline Quartz (SiO2)
Chert (Flint)
Microcrystalline Silicon Dioxide (SiO2)
Chert (Jasper)
Microcrystalline Quartz (SiO2)
Chert (often called Flint)
Microcrystalline or cryptocrystalline Quartz (SiO2)
Chert
Chert (Microcrystalline Quartz, SiO2)
Polished amber
Fossilized tree resin; chiefly terpenoid polymers (succinite)
Petrified Wood
Silicified Wood (SiO2)
Agate (Moss or Green Agate)
Silicon Dioxide (SiO2)
Chert (Jasper)
Microcrystalline Quartz (SiO2)
Moss Agate
Chalcedony (Silicon Dioxide, SiO2) with inclusions
Orange Calcite
Calcium Carbonate (CaCO3)
Moss Agate / Chalcedony
Silicon Dioxide (SiO2)
Chert (Nodule)
Microcrystalline Quartz (SiO2)
Amber
Fossilized Tree Resin (Successite)
Pink Opal
Hydrated Silica (SiO2·nH2O) with Palygorskite/Sepiolite inclusions
Jasper (Red Jasper)
Silicon Dioxide (SiO₂)
Chert (Jasper variety)
Silicon Dioxide (SiO2)
Chert / Flint
Silicon Dioxide (SiO2)
Chert (Jasper/Flint variety)
Silicon Dioxide (SiO2)
Moss Agate
Cryptocrystalline Quartz (SiO2 with Manganese or Iron Oxide inclusions)
Chert (Red Jasper variant)
Microcrystalline Quartz (SiO2)
Chert (Yellow Jasper/Flint)
Silicon Dioxide (SiO2)
Pearl
Calcium Carbonate (Aragonite/Calcite) with Conchiolin (CaCO3)
Chert (often called Flint)
Microcrystalline Quartz (SiO2)
Chert
Microcrystalline Quartz (SiO2)
Chalcedony
Cryptocrystalline Quartz (SiO2)
Chert (Jasper/Flint variety)
Microcrystalline Quartz (SiO2)
Chert (Black Chert/Flint)
Silicon Dioxide (SiO2)
Chert (Jasper)
Microcrystalline Quartz (SiO2)
Petrified Wood
Silicified wood (principally SiO2)
Raw amber
Fossilized tree resin; primarily polymerized terpenoid resin (succinite when Baltic-type)
Carved red coral bead (likely coral or coral-colored resin)
Corallium spp. (precious coral; calcium carbonate, CaCO₃)
Amber
Succinite
Chert (Black Chert/Flint)
Silicon Dioxide (SiO2)
Chert (specifically Flint)
Silicon Dioxide (SiO2)
Black Jasper
Silicon Dioxide (SiO2) with impurities
Chert (Jasper)
Cryptocrystalline Quartz (SiO2)
Likely amber or amber-like resin fragment
Amber (fossilized plant resin), commonly succinite; identification uncertain from the image
Moss Agate
SiO2 (Cryptocrystalline Quartz)
Polished amber-like agate or jasper carving
Likely chalcedony (microcrystalline SiO₂), possibly iron-stained carnelian/jasper; exact identification requires testing
Fancy Jasper
Jasper (Cryptocrystalline Quartz, SiO2)
Moss Agate
Silicon Dioxide (SiO2) with inclusions