Chert (Flint)
Microcrystalline or cryptocrystalline quartz (SiO2)
sedimentary
Category
Mineral And Organic Gemstone
Browse mineral and organic gemstone specimens identified by the Rock Identifier community.
Yellow Chert (Jasper/Flint variety)
Microcrystalline Quartz (SiO2)
sedimentary
Chert (Iron-rich variety)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
sedimentary
Asphalt / Bituminous Aggregate
Bituminous mixture (Hydrocarbon-based sediment)
sedimentary
Quartz Geode
Silicon Dioxide (SiO2)
sedimentary
Petrified Wood
Silicified Wood (primarily Quartz/Chalcedony, formula SiO2)
sedimentary
Peridot
Olivine (Mg, Fe)2SiO4
mineral
Citrine Quartz
Silicon Dioxide (SiO2)
mineral
Citrine
Crystalline Quartz (SiO2) with iron impurities
mineral
Industrial Diamond (Bort or Boart)
Diamond (pure Carbon, C)
mineral
Malachite with Chrysocolla
Copper carbonate hydroxide (Cu2CO3(OH)2) and Hydrated copper silicate (Cu,Al)2H2Si2O5(OH)4·nH2O
mineral
Prehnite
Prehnite (Ca2Al(AlSi3O10)(OH)2)
mineral
Prehnite
Prehnite (Ca2Al(AlSi3O10)(OH)2)
mineral
Astrophyllite
Potassium Sodium Iron Manganese Titanium Silicate Hydroxide (K3NaFe7Ti2Si8O24(OH)7)
mineral
Spiny Oyster Shell
Spondylus (Calcium Carbonate, CaCO3)
mineral
Chert (often called Flint when dark)
Chert (Microcrystalline or Cryptocrystalline Silica, SiO2)
sedimentary
Green Moss Agate
Silicon Dioxide (SiO2) with inclusions of hornblende or chlorite
sedimentary
Amber
Succinite (fossilized resin)
mineral
Baltic Amber (Butterscotch variety)
Succinite
Organic Gemstone/Mineraloid
Baltic Amber (Butterscotch or Egg Yolk Variety)
Succinite (C10H16O)
Organic Gemstone (Mineraloid)
Amethyst
Amethyst (Silicon Dioxide, SiO2)
mineral
Potassium-Rich Silicate Clay (inferred from biological context)
Phyllosilicate group (likely Illite or Smectite within surrounding soil substrate)
mineral
Chert (Jasper/Flint variety)
Microcrystalline Quartz (SiO2)
sedimentary
Moss Agate
Silicon Dioxide (SiO2) with inclusions
mineral
Fluorite with Rhodochrosite
Fluorite (CaF2) and Rhodochrosite (MnCO3)
Mineral
Diamond
Native Carbon (C)
mineral
Septarian Nodule (Dragon Stone)
Septarian concretion (composition: CaCO3 - Calcite, Aragonite, and Siderite/Limestone)
sedimentary
Petrified Wood
Silicified Wood (SiO2)
sedimentary
Coral Fossil (Scleractinia)
Scleractinia (Order), primarily CaCO3 (Aragonite or Calcite)
sedimentary
Petrified Wood
Silicified Wood (SiO2)
sedimentary
Banded Chert
Microcrystalline Quartz (SiO2)
sedimentary
Petrified Wood
Silicified Wood / Chalcedony (SiO2)
mineral
Chert (Commonly known as Flint)
Microcrystalline Quartz (SiO2)
sedimentary
Orange Calcite
Calcium Carbonate (CaCO3)
mineral
Green Calcite
Calcium Carbonate (CaCO3)
mineral
Limestone with Calcite Veins
Calcium Carbonate (CaCO3)
sedimentary
Granite (Weathered)
Course-grained Intrusive Igneous Rock
igneous
Picture Jasper
Silicon Dioxide (SiO2) with iron oxide and clay inclusions
sedimentary
Amber
Succinite (Carbon-based organic compound; approximate formula C10H16O)
Mineraloid
Chert (Flint variety)
Microcrystalline or cryptocrystalline Quartz (SiO2)
sedimentary
Quartzite with inclusions
Quartzite
metamorphic
Chert (with Quartz Vein)
Chert (Siliceous sedimentary rock, predominantly Microcrystalline Quartz SiO2)
sedimentary