Rock Identifier

Category

Organic Gemstone (Sedimentary Classification)

Browse organic gemstone (sedimentary classification) specimens identified by the Rock Identifier community.

Quartz (specifically Milky Quartz/Quartzite) (Silicon Dioxide (SiO2)) — Mineral

Quartz (specifically Milky Quartz/Quartzite)

Silicon Dioxide (SiO2)

Citrine (Silicon dioxide (SiO2) - yellow quartz variety) — mineral

Citrine

Silicon dioxide (SiO2) - yellow quartz variety

Garnet-Bearing Gneiss (Almandine-Garnet Gneiss) — metamorphic

Garnet-Bearing Gneiss

Almandine-Garnet Gneiss

Banded Calcite (variety Honey Calcite / Chocolate Calcite) (Calcium Carbonate (CaCO3)) — mineral

Banded Calcite (variety Honey Calcite / Chocolate Calcite)

Calcium Carbonate (CaCO3)

Smoky Quartz (Silicon Dioxide (SiO2)) — mineral

Smoky Quartz

Silicon Dioxide (SiO2)

Petrified Wood (Silicified Wood (SiO2)) — metamorphic

Petrified Wood

Silicified Wood (SiO2)

Petrified Wood (Silicified wood (Quartz, SiO2)) — metamorphic

Petrified Wood

Silicified wood (Quartz, SiO2)

Jasper (Green/Yellow Moss Jasper) (Silicon Dioxide (SiO2)) — mineral

Jasper (Green/Yellow Moss Jasper)

Silicon Dioxide (SiO2)

Moss Agate (Silicon Dioxide (SiO2) with inclusions) — mineral

Moss Agate

Silicon Dioxide (SiO2) with inclusions

Diamond in Gold Setting (Diamond (C - pure carbon)) — mineral

Diamond in Gold Setting

Diamond (C - pure carbon)

Petrified Wood (Silicified Wood) (Silicified Wood / Silicon Dioxide (SiO2)) — metamorphic

Petrified Wood (Silicified Wood)

Silicified Wood / Silicon Dioxide (SiO2)

Petrified Wood (Silicified Wood / Chalcedony (SiO2)) — mineral

Petrified Wood

Silicified Wood / Chalcedony (SiO2)

Petrified Wood (Silicified Wood (primarily SiO₂ - Silicon Dioxide)) — metamorphic

Petrified Wood

Silicified Wood (primarily SiO₂ - Silicon Dioxide)

Garnet-bearing Schist (Almandine Garnet (Fe3Al2(SiO4)3) in Mica Schist) — metamorphic

Garnet-bearing Schist

Almandine Garnet (Fe3Al2(SiO4)3) in Mica Schist

Amethyst (Faceted Gemstone) (Silicon Dioxide (SiO2) with iron impurities) — mineral

Amethyst (Faceted Gemstone)

Silicon Dioxide (SiO2) with iron impurities

Aquamarine (Beryl (Be3Al2Si6O18)) — mineral

Aquamarine

Beryl (Be3Al2Si6O18)

Yellow Jasper (Jasper (Silicon Dioxide, SiO2)) — sedimentary (or mineraloid)

Yellow Jasper

Jasper (Silicon Dioxide, SiO2)

sedimentary (or mineraloid)

Red Jasper or Chert (Jasper (SiO2, a variety of chalcedony with iron oxide impurities), Chert (SiO2)) — sedimentary

Red Jasper or Chert

Jasper (SiO2, a variety of chalcedony with iron oxide impurities), Chert (SiO2)

Quartz (likely milky/rose quartz variety) (Quartz (SiO2 - Silicon Dioxide)) — Mineral

Quartz (likely milky/rose quartz variety)

Quartz (SiO2 - Silicon Dioxide)

Tanzanite (Blue Zoisite (Ca2Al3(SiO4)(Si2O7)O(OH))) — mineral

Tanzanite

Blue Zoisite (Ca2Al3(SiO4)(Si2O7)O(OH))

Peridot (Olivine (Mg, Fe)2SiO4) — Mineral

Peridot

Olivine (Mg, Fe)2SiO4

Petrified Wood (Silicified Wood (SiO2)) — metamorphic

Petrified Wood

Silicified Wood (SiO2)

Emerald (Faceted Gemstone) (Beryl (Be3Al2Si6O18 with Chromium/Vanadium impurities)) — mineral

Emerald (Faceted Gemstone)

Beryl (Be3Al2Si6O18 with Chromium/Vanadium impurities)

Jadeite and Assorted Corundum (Ruby/Sapphire) / Beryl (Emerald) (Jadeite (NaAlSi2O6), Ruby/Sapphire (Al2O3), Emerald (Be3Al2(SiO3)6)) — mineral

Jadeite and Assorted Corundum (Ruby/Sapphire) / Beryl (Emerald)

Jadeite (NaAlSi2O6), Ruby/Sapphire (Al2O3), Emerald (Be3Al2(SiO3)6)

Amethyst (Silicon Dioxide (SiO2) with iron impurities) — mineral

Amethyst

Silicon Dioxide (SiO2) with iron impurities

Aura Rose Quartz (SiO2 (Silicon Dioxide with Titanium/Gold coating)) — mineral

Aura Rose Quartz

SiO2 (Silicon Dioxide with Titanium/Gold coating)

Jasper, Agate, Quartz Mix (Polished Beads) (SiO₂ (Silicon Dioxide) for Quartz. Jasper and Agate are cryptocrystalline varieties of Quartz.) — Mineral/Semiprecious Gemstone (variety of Quartz)

Jasper, Agate, Quartz Mix (Polished Beads)

SiO₂ (Silicon Dioxide) for Quartz. Jasper and Agate are cryptocrystalline varieties of Quartz.

Mineral/Semiprecious Gemstone (variety of Quartz)

Peridot (Olivine (Mg, Fe)2SiO4) — mineral

Peridot

Olivine (Mg, Fe)2SiO4

Chert (Jasper variety) (Silicon Dioxide (SiO2) - Microcrystalline Quartz) — sedimentary

Chert (Jasper variety)

Silicon Dioxide (SiO2) - Microcrystalline Quartz

Chalcedony (Banded/Mottled Variety) (Chalcedony (a cryptocrystalline variety of Quartz, SiO2)) — Mineral

Chalcedony (Banded/Mottled Variety)

Chalcedony (a cryptocrystalline variety of Quartz, SiO2)

Quartz (Quartz (SiO₂)) — Mineral

Quartz

Quartz (SiO₂)

Petrified Wood (Silicified Wood (SiO2)) — mineral

Petrified Wood

Silicified Wood (SiO2)

Petrified Wood (Silicified wood, primarily composed of Quartz (SiO2)) — Mineral, often found in sedimentary deposits

Petrified Wood

Silicified wood, primarily composed of Quartz (SiO2)

Mineral, often found in sedimentary deposits

Chalcedony (Agate) (Silicon Dioxide (SiO2)) — mineral

Chalcedony (Agate)

Silicon Dioxide (SiO2)

Aventurine (likely Green Aventurine) (Silicon Dioxide (SiO2) with mineral inclusions) — Mineral/Mineraloid within a rock matrix

Aventurine (likely Green Aventurine)

Silicon Dioxide (SiO2) with mineral inclusions

Mineral/Mineraloid within a rock matrix

Opal (Hydrous silicon dioxide (SiO2·nH2O)) — mineral

Opal

Hydrous silicon dioxide (SiO2·nH2O)

Ambergris (Geological/Organic Specimen) (Ambra grisea (Produced by Physeter macrocephalus)) — organic material

Ambergris (Geological/Organic Specimen)

Ambra grisea (Produced by Physeter macrocephalus)

organic material

Spiny Oyster Shell (Spondylus (Calcium Carbonate, CaCO3)) — mineral

Spiny Oyster Shell

Spondylus (Calcium Carbonate, CaCO3)

Moss Agate (Silicon Dioxide (SiO2) with inclusions of hornblende, chlorite, or manganese/iron oxides) — mineral

Moss Agate

Silicon Dioxide (SiO2) with inclusions of hornblende, chlorite, or manganese/iron oxides

Amethyst Sage Agate (Silicon Dioxide (SiO2) with trace minerals (Manganese/Iron oxides)) — mineral

Amethyst Sage Agate

Silicon Dioxide (SiO2) with trace minerals (Manganese/Iron oxides)

Almandine Garnet in Matrix (Almandine, Fe3Al2(SiO4)3) — metamorphic

Almandine Garnet in Matrix

Almandine, Fe3Al2(SiO4)3

Quartz (Silicon Dioxide (SiO2)) — Mineral

Quartz

Silicon Dioxide (SiO2)