Chert (variations include Flint/Jasper)
Cryptocrystalline Quartz (SiO2)
Category
Browse organic gemstone (mineraloid) specimens identified by the Rock Identifier community.
Chert (variations include Flint/Jasper)
Cryptocrystalline Quartz (SiO2)
Chert (Flint)
Chert (Silicon Dioxide, SiO2)
Chert (Jasper/Flint variety)
Microcrystalline Quartz (SiO2)
Chert (often called Flint when dark)
Chert (Microcrystalline or Cryptocrystalline Silica, SiO2)
Chert (Flint variety)
Microcrystalline or cryptocrystalline Quartz (SiO2)
Chert (often called Flint or Jasper)
Chert (Microcrystalline or Cryptocrystalline Silica, SiO2)
Red Jasper
Jasper (Silicon Dioxide, SiO2 with iron oxide impurities)
Chert (Commonly known as Flint)
Microcrystalline Quartz (SiO2)
Chert / Flint
Cryptocrystalline Quartz (Silicon Dioxide, SiO2)
Chert / Flint
Cryptocrystalline Quartz (SiO2)
Chert / Flint
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Chert (varieties include Flint and Jasper)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Chert (Jasper variety)
Silicon Dioxide (SiO2)
Chert (specifically Flint or Jasper variant)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Chert (and Chalcedony)
Microcrystalline Quartz (SiO2)
Chert (Cherty Flint/Jasper variety)
Microcrystalline or cryptocrystalline Quartz (SiO2)
Red Coral
Corallium rubrum (Calcium Carbonate, CaCO3)
Pyrite
Pyrite (Iron sulfide, FeS₂)
Coral (Precious Coral)
Corallium rubrum (Red Coral), Paracorallium japonicum (Momo Coral), Pleurocorallium elatius (Sardinian Coral), various other species within the Corallidae family. Chemically, it's primarily Calcium Carbonate (CaCO 3 ).
Chert (Jasper variation)
Chert (SiO2)
Banded Chert
Cryptocrystalline Quartz (SiO2)
Mother of Pearl (Nacre)
Calcium Carbonate (primarily aragonite, with conchiolin)
Amber (Simulated/Faturan Style)
Resin mix (Likely Phenolic/Celluloid if synthetic, Succinite if natural)
Baltic Amber (Butterscotch or Egg Yolk Variety)
Fossilized Tree Resin (Succinite); Approximate formula: C10H16O
Pyrite
Pyrite (FeS2)
Hand-Drawn Trading Card (Amateur Artwork)
Cellulose-based substrate with wax/graphite/ink deposit (n/a for minerals)
Amber
Fossilized Tree Resin (Amorphous Hydrocarbon)
Opalite (a synthetic glass, often confused with Opal)
Silicon dioxide glass (SiO2nH2O, for natural opal)
Baroque Pearl (and potentially a small Sapphire/Blue Topaz)
Pearl: Calcium Carbonate (aragonite or calcite) with conchiolin. Sapphire: Aluminum Oxide (Al2O3). Blue Topaz: Al2SiO4(F,OH)2.
Chert / Flint
Chert (varieties include Flint)
Pyrite
Pyrite (Iron Disulfide), FeS2
Baltic Amber (Butterscotch or Egg Yolk Variety)
Succinite (C10H16O)
Red Coral
Corallium rubrum (for precious red coral), although other species like Corallium japonicum and Paracorallium are also used.
Citrine
Silicon Dioxide (SiO2)
Manganese Dendrite on Siltstone
Manganese Oxide (pyrolusite or psilomelane) Dendrites
Labradorite
(Ca, Na)(Al, Si)4O8 (Calcium Sodium Aluminum Silicate)
Cat's Eye Moonstone (Feldspar)
Orthoclase (KAlSi3O8) with Albite (NaAlSi3O8) inclusions
Pearl
Calcium Carbonate (Aragonite) - CaCO3
Hypersthene
Enstatite (Hypersthene variety), (Mg,Fe)SiO3
Charoite
Charoite (K(Ca,Na)2Si4O10(OH,F)·nH2O)
Dendritic Agate (or Dendritic Opal)
SiO2 (for Agate), SiO2·nH2O (for Opal)
Blue glass-like tumbled specimen
Most likely cobalt-blue slag glass or manufactured glass; not confidently identifiable as a natural mineral from the image