Chert (Black Chert/Flint)
Microcrystalline quartz (SiO2)
Category
Browse mineralloid (organic gemstone) specimens identified by the Rock Identifier community.
Chert (Black Chert/Flint)
Microcrystalline quartz (SiO2)
Polished amber
Amber (fossilized plant resin; primarily organic polymerized terpenes)
Herkimer Diamond
Quartz (Silica - SiO2)
Chert (specifically White Chert or Flint)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Baltic Amber (Butterscotch or Egg Yolk Variety)
Succinite (chemical formula: C10H16O)
Chert (Smoky variety)
Microcrystalline Quartz (SiO2)
Tufa Rock and Tumbled Gemstones
Calcareous Tufa (Calcium Carbonate, CaCO3)
Pearl
Aragonite and Conchiolin (CaCO3 + organic protein)
Chert (and Flint variant)
Microcrystalline or cryptocrystalline Quartz (SiO2)
Chert (specifically Flint or Jasper variant)
Cryptocrystalline Quartz (SiO2)
Chert (Jasper/Chalcedony)
Microcrystalline Silica (SiO2)
Picasso Jasper (or Picasso Marble)
Metamorphosed Limestone (Calcium Carbonate, CaCO3, with impurities)
Polished fossiliferous limestone
Bioclastic carbonate rock, primarily calcite (CaCO₃)
Chert / Flint
Cryptocrystalline Quartz (SiO2)
Moss Agate
Silicon Dioxide (SiO2) with inclusions of manganese or iron oxides
Chert (often called Flint in archaeological contexts)
Silicon Dioxide (SiO2)
Chert (Banded Variety)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Tumbled amber
Amber (fossilized plant resin), chiefly polymerized diterpenoid resin
Fancy Jasper
Silicon dioxide (SiO2)
Chert (including Flint and Jasper variants)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Chert (with Limestone matrix)
Chert (Silica: SiO2)
Plume Agate
Cryptocrystalline Quartz (SiO2)
Chert (Flint variety)
Chert (Cryptocrystalline Quartz, SiO2)
Chert (specifically Red Chert or Jasper)
Microcrystalline Quartz (SiO2)
Chert (Chalcedony/Jasper)
Microcrystalline Quartz (SiO2)
Petrified Wood
Silicified Wood (primarily SiO2)
Cultured freshwater pearls
Pearl; primarily aragonite (CaCO₃) in nacre with an organic conchiolin matrix
Amber (likely rough amber or copal)
Fossilized tree resin; chiefly an organic polymer with terpenoid remnants
Amber
Fossilized plant resin; primarily organic terpenoid compounds (not a mineral)
Amber
Succinite (specifically for Baltic amber); Approximate formula: C10H16O
Petrified Wood
Silicified Wood (SiO2)
Amber
Succinite (a fossilized organic resin containing succinic acid)
Chert (and/or Chalcedony)
Microcrystalline Silica (SiO2)
Chert (variations include Flint/Novaculite)
Chert (formula: SiO2)
Chert (often called Flint or Jasper)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Jasper (specifically Yellow Jasper and Red Jasper)
Silicon Dioxide (SiO2) with iron oxide inclusions
Banded Chert (Flint/Jasper variety)
Microcrystalline Quartz (SiO2)
Jasper
Silicon Dioxide (SiO2) with impurities
Chert (Flint)
Chert (Microcrystalline Quartz, SiO2)
Chert (Yellow Jasper)
Microcrystalline Quartz (SiO2)
Chert (Flint Nodular)
Chert (Silicon dioxide, SiO2)
Chert (Iron-stained)
Chert (SiO2)