Rock Identifier

Category

Organic Gemstone (Sedimentary Classification)

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

Chrysoprase (Nickel-bearing Chalcedony (SiO2 with Ni impurities)) — mineral

Chrysoprase

Nickel-bearing Chalcedony (SiO2 with Ni impurities)

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

Amethyst

Silicon Dioxide (SiO2) with iron impurities

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

Massive Milky Quartz

Quartz (Silicon Dioxide, SiO2)

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

Milky Quartz

Quartz (Silicon Dioxide - SiO2)

Obsidian (Volcanic Glass (predominantly SiO2)) — igneous

Obsidian

Volcanic Glass (predominantly SiO2)

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

Prehnite

Prehnite (Ca2Al(AlSi3O10)(OH)2)

Nephrite Jade (Nephrite (Ca2(Mg, Fe)5Si8O22(OH)2)) — metamorphic

Nephrite Jade

Nephrite (Ca2(Mg, Fe)5Si8O22(OH)2)

Tiger's Eye (Pseudomorph of quartz after crocidolite (SiO2)) — metamorphic

Tiger's Eye

Pseudomorph of quartz after crocidolite (SiO2)

Almandine Garnet (Almandine, Fe3Al2(SiO4)3) — mineral

Almandine Garnet

Almandine, Fe3Al2(SiO4)3

Tiger's Eye (Pseudomorph of Quartz after Crocidolite (SiO2 with iron oxide inclusions)) — metamorphic

Tiger's Eye

Pseudomorph of Quartz after Crocidolite (SiO2 with iron oxide inclusions)

Fluorite (Calcium Fluoride (CaF2)) — mineral

Fluorite

Calcium Fluoride (CaF2)

Epidote (Epidote (Ca2(Al2,Fe)(SiO4)(Si2O7)O(OH))) — metamorphic

Epidote

Epidote (Ca2(Al2,Fe)(SiO4)(Si2O7)O(OH))

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

Milky Quartz

Crystalline Silicon Dioxide (SiO2)

Tiger's Eye (Silicon Dioxide with inclusions (SiO2)) — mineral

Tiger's Eye

Silicon Dioxide with inclusions (SiO2)

Vesicular Basalt with Opal or Quartz (Vesicular Basalt (Amorphous SiO2.nH2O if Opal)) — igneous

Vesicular Basalt with Opal or Quartz

Vesicular Basalt (Amorphous SiO2.nH2O if Opal)

Aquamarine (Rough) (Beryl (Be3Al2Si6O18)) — mineral

Aquamarine (Rough)

Beryl (Be3Al2Si6O18)

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

Amethyst

Amethyst (Silicon Dioxide - SiO2 with iron impurities)

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

Clear Quartz (Rock Crystal)

Silicon Dioxide (SiO2)

Tiger's Eye (Pseudomorph of Quartz after Crocidolite (SiO2 with iron oxide inclusions)) — metamorphic

Tiger's Eye

Pseudomorph of Quartz after Crocidolite (SiO2 with iron oxide inclusions)

Tektite (Indochinite) (Tektite (Amorphous Silica Glass)) — igneous

Tektite (Indochinite)

Tektite (Amorphous Silica Glass)

Alexandrite in Matrix (Chrysoberyl (BeAl2O4 with Chromium)) — mineral

Alexandrite in Matrix

Chrysoberyl (BeAl2O4 with Chromium)

Green Aventurine (Green Quartz) (Silicon Dioxide (SiO2) with inclusions of Fuchsite (K(Al,Cr)2(AlSi3O10)(OH)2)) — Mineral/Metamorphic rock

Green Aventurine (Green Quartz)

Silicon Dioxide (SiO2) with inclusions of Fuchsite (K(Al,Cr)2(AlSi3O10)(OH)2)

Mineral/Metamorphic rock

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

Olivine (Peridot)

Olivine Group (Mg,Fe)2SiO4

Yellow Quartz (Silicon Dioxide (SiO2)) — mineral

Yellow Quartz

Silicon Dioxide (SiO2)

Amazonite (Microline Feldspar (KAlSi3O8)) — mineral

Amazonite

Microline Feldspar (KAlSi3O8)

Milky Quartz (or Iron-Stained Quartz) (Quartz (Silicon Dioxide, SiO2)) — mineral

Milky Quartz (or Iron-Stained Quartz)

Quartz (Silicon Dioxide, SiO2)

Tiger's Eye (Pseudomorph of quartz after crocidolite (SiO2 with iron inclusions)) — metamorphic

Tiger's Eye

Pseudomorph of quartz after crocidolite (SiO2 with iron inclusions)

White Quartz (Mushroom Carving) (Quartz (Silicon Dioxide - SiO2)) — mineral

White Quartz (Mushroom Carving)

Quartz (Silicon Dioxide - SiO2)

Sodalite (Sodalite (Na8(Al6Si6O24)Cl2)) — mineral

Sodalite

Sodalite (Na8(Al6Si6O24)Cl2)

Tiger's Eye (Pseudomorph of Quartz after Crocidolite (SiO2)) — metamorphic

Tiger's Eye

Pseudomorph of Quartz after Crocidolite (SiO2)

Citrine (Quartz variant) (SiO2 (Silicon Dioxide)) — mineral

Citrine (Quartz variant)

SiO2 (Silicon Dioxide)

Obsidian (Obsidian (Amorphous volcanic glass, predominantly SiO2)) — igneous

Obsidian

Obsidian (Amorphous volcanic glass, predominantly SiO2)

Amethyst (Amethyst (Silicon Dioxide SiO2 + Fe4+)) — mineral

Amethyst

Amethyst (Silicon Dioxide SiO2 + Fe4+)

Rose Quartz (Silicon dioxide (SiO2) with trace amounts of titanium, iron, or manganese) — mineral

Rose Quartz

Silicon dioxide (SiO2) with trace amounts of titanium, iron, or manganese

Peach Moonstone (Feldspar variety) (Orthoclase Feldspar (KAlSi3O8) with inclusions) — mineral

Peach Moonstone (Feldspar variety)

Orthoclase Feldspar (KAlSi3O8) with inclusions

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

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

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

Quartz (Milky Quartz)

Silicon Dioxide (SiO2)

Black Tourmaline (Schorl (NaFe3Al6(BO3)3Si6O18(OH)4)) — mineral

Black Tourmaline

Schorl (NaFe3Al6(BO3)3Si6O18(OH)4)

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

White Quartz (Milky Quartz)

Silicon Dioxide (SiO2)

Amazonite (Microcline (variety Amazonite), K(AlSi3O8)) — mineral

Amazonite

Microcline (variety Amazonite), K(AlSi3O8)

Quartzite (Quartzite (SiO2)) — metamorphic

Quartzite

Quartzite (SiO2)

Labradorite (Labradorite (Ca,Na)(Al,Si)4O8) — mineral

Labradorite

Labradorite (Ca,Na)(Al,Si)4O8