Rock Identifier

Category

Organic Gemstone (Often Associated With Sedimentary Sequences)

Browse organic gemstone (often associated with sedimentary sequences) specimens identified by the Rock Identifier community.

Quartz (Silicon Dioxide (SiO2)) — Mineral

Quartz

Silicon Dioxide (SiO2)

Sandstone (Quartzite-rich) (Clastic Sedimentary Rock (primarily SiO2)) — sedimentary

Sandstone (Quartzite-rich)

Clastic Sedimentary Rock (primarily SiO2)

Prehnite (Prehnite (Ca2Al(AlSi3O10)(OH)2)) — mineral

Prehnite

Prehnite (Ca2Al(AlSi3O10)(OH)2)

Sapphire (Corundum) (Corundum (Al2O3), variety Sapphire) — Mineral

Sapphire (Corundum)

Corundum (Al2O3), variety Sapphire

Hypersthene (Enstatite (Hypersthene variety), (Mg,Fe)SiO3) — mineral

Hypersthene

Enstatite (Hypersthene variety), (Mg,Fe)SiO3

Quartz (Silicon Dioxide (SiO2)) — Mineral

Quartz

Silicon Dioxide (SiO2)

Rough Quartz (var. Citrine or Yellow Quartz) (Silicon Dioxide (SiO2)) — mineral

Rough Quartz (var. Citrine or Yellow Quartz)

Silicon Dioxide (SiO2)

Sunstone (Feldspar variety) (Plagioclase Feldspar (Na,Ca)(Al,Si)4O8) — mineral

Sunstone (Feldspar variety)

Plagioclase Feldspar (Na,Ca)(Al,Si)4O8

Hematite Beads (Hematite (Fe2O3)) — Mineral

Hematite Beads

Hematite (Fe2O3)

Banded Calcite (often sold as Caribbean Calcite or Honey Calcite) (Calcium Carbonate (CaCO3)) — mineral

Banded Calcite (often sold as Caribbean Calcite or Honey Calcite)

Calcium Carbonate (CaCO3)

Green Quartzite (Quartzite (SiO2)) — metamorphic

Green Quartzite

Quartzite (SiO2)

Emerald and Diamond (Jewelry Setting) (Beryl (Be3Al2Si6O18 with Chromium/Vanadium impurities) and Carbon (C)) — mineral

Emerald and Diamond (Jewelry Setting)

Beryl (Be3Al2Si6O18 with Chromium/Vanadium impurities) and Carbon (C)

Chert (Gravel) (Chert (Cryptocrystalline silicon dioxide, SiO2)) — sedimentary

Chert (Gravel)

Chert (Cryptocrystalline silicon dioxide, SiO2)

Sandstone (Clastic sedimentary rock (primarily SiO2)) — sedimentary

Sandstone

Clastic sedimentary rock (primarily SiO2)

Fuchsite Quartzite (Green Quartzite) (Fuchsite-bearing Quartzite (K(Al,Cr)2(AlSi3O10)(OH)2 + SiO2)) — metamorphic

Fuchsite Quartzite (Green Quartzite)

Fuchsite-bearing Quartzite (K(Al,Cr)2(AlSi3O10)(OH)2 + SiO2)

Smoky Quartz (Silicon Dioxide (SiO2)) — mineral

Smoky Quartz

Silicon Dioxide (SiO2)

Chrysocolla (Chrysocolla (Cu2-xAlx(H2-xSi2O5)(OH)4·nH2O)) — mineral

Chrysocolla

Chrysocolla (Cu2-xAlx(H2-xSi2O5)(OH)4·nH2O)

Sandstone (Sandstone (Clastic Sedimentary Rock)) — Sedimentary Rock

Sandstone

Sandstone (Clastic Sedimentary Rock)

Sedimentary Rock

Pebble (likely Quartz or Chert) (SiO₂ (Silicon Dioxide) - referring to the likely main mineral composition, Quartz. If it's chert, the scientific name remains SiO₂ with a microcrystalline structure.) — Sedimentary Rock

Pebble (likely Quartz or Chert)

SiO₂ (Silicon Dioxide) - referring to the likely main mineral composition, Quartz. If it's chert, the scientific name remains SiO₂ with a microcrystalline structure.

Sedimentary Rock

Agate Geode Slice (with Druzy Quartz) (Silicon Dioxide (SiO2)) — mineral

Agate Geode Slice (with Druzy Quartz)

Silicon Dioxide (SiO2)

Sodalite (Na8(Al6Si6O24)Cl2) — mineral

Sodalite

Na8(Al6Si6O24)Cl2

Peridot (Olivine) (Magnesium Iron Silicate (Mg, Fe)2SiO4) — mineral

Peridot (Olivine)

Magnesium Iron Silicate (Mg, Fe)2SiO4

Red Jasper (Jasper (Silica with Iron Oxide inclusions), SiO2) — sedimentary

Red Jasper

Jasper (Silica with Iron Oxide inclusions), SiO2

Malachite (Malachite (Cu2CO3(OH)2)) — mineral

Malachite

Malachite (Cu2CO3(OH)2)

Milky Quartz (Quartz (Silicon Dioxide, SiO2)) — mineral

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

Rhodonite (Manganese Silicate (Mn,Fe,Mg,Ca)SiO3) — mineral

Rhodonite

Manganese Silicate (Mn,Fe,Mg,Ca)SiO3

Zoisite with Ruby (Anyolite (Ca2Al3(SiO4)3(OH) with Al2O3:Cr)) — metamorphic

Zoisite with Ruby

Anyolite (Ca2Al3(SiO4)3(OH) with Al2O3:Cr)

Chalk (Calcareous Ooze (composed primarily of coccoliths)) — Sedimentary Rock

Chalk

Calcareous Ooze (composed primarily of coccoliths)

Sedimentary Rock

Banded Quartzite (Quartzite (SiO2 with impurities)) — metamorphic

Banded Quartzite

Quartzite (SiO2 with impurities)

Chert (Flint nodule) (Microcrystalline or Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (Flint nodule)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Carnelian (Chalcedony (cryptocrystalline quartz), SiO2 (Silicon Dioxide)) — Mineral

Carnelian

Chalcedony (cryptocrystalline quartz), SiO2 (Silicon Dioxide)

Iolite (Cordierite) (Cordierite (Magnesium iron aluminum cyclosilicate), Mg2Al4Si5O18) — metamorphic

Iolite (Cordierite)

Cordierite (Magnesium iron aluminum cyclosilicate), Mg2Al4Si5O18

Clear Quartz (Rock Crystal) (Silicon Dioxide (SiO2)) — mineral

Clear Quartz (Rock Crystal)

Silicon Dioxide (SiO2)

Amethyst Geode (Silicon Dioxide (SiO2) - Amethyst variety of Quartz) — mineral

Amethyst Geode

Silicon Dioxide (SiO2) - Amethyst variety of Quartz

Gneiss (Gneiss) — metamorphic

Gneiss

Gneiss

Chalcedony (Yellow/Honey variety) (Microcrystalline Quartz (SiO2)) — mineral

Chalcedony (Yellow/Honey variety)

Microcrystalline Quartz (SiO2)

Sandstone (Arenite (Sedimentary Rock)) — sedimentary

Sandstone

Arenite (Sedimentary Rock)

Quartz with Iron Stains (Quartz (SiO2) with iron oxide/hydroxide staining) — Mineral

Quartz with Iron Stains

Quartz (SiO2) with iron oxide/hydroxide staining

Green Calcite (Onyx Marble) (Calcium Carbonate (CaCO3)) — mineral

Green Calcite (Onyx Marble)

Calcium Carbonate (CaCO3)

Clear Quartz (Silicon Dioxide (SiO2)) — mineral

Clear Quartz

Silicon Dioxide (SiO2)

Bloodstone / Heliotrope (Silicon dioxide (SiO2) with inclusions) — Mineral (variety of Chalcedony)

Bloodstone / Heliotrope

Silicon dioxide (SiO2) with inclusions

Mineral (variety of Chalcedony)

Amazonite (Amazonite (KAlSi3O8 - Microcline)) — mineral

Amazonite

Amazonite (KAlSi3O8 - Microcline)