Black Marble with Quartz Veining
Metamorphosed Limestone (Recrystallized CaCO3)
metamorphic
Category
Organic Gemstone (Often Associated With Sedimentary Sequences)
Browse organic gemstone (often associated with sedimentary sequences) specimens identified by the Rock Identifier community.
Septarian Nodule (Dragon Stone)
Septarian Nodule (Calcium Carbonate/Aragonite/Calcite Concretion)
sedimentary
Ruby
Corundum (Al2O3 with Chromium traces)
mineral
Quartz (Pebble)
Quartz (SiO₂)
Mineral
Citrine
Crystalline Quartz (SiO2) with iron impurities
mineral
Chert (often called Flint when dark)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
sedimentary
Milky Quartz
Silicon Dioxide (SiO2)
mineral
Jasper
Silicon dioxide (SiO2) with iron inclusions
sedimentary
Quartz (Milky/Gray variety)
Silicon Dioxide (SiO2)
mineral
Amber
Succinite (fossilized tree resin)
mineraloid / sedimentary organic material
Limestone
Calcareous sedimentary rock (primarily CaCO3)
sedimentary
Quartz
Quartz (SiO2 - Silicon Dioxide)
Mineral
Shale
Fissile mudrock (composed of clay-sized particles and detrital grains)
sedimentary
Sandstone (Ferruginous)
Arenite (primarily SiO2 with Iron Oxide cement)
sedimentary
Sandstone (Ferruginous)
Clastic Sedimentary Rock (SiO2 with Fe2O3/FeOOH cement)
sedimentary
Red Jasper
Silicon Dioxide with Iron Oxide (SiO2)
sedimentary
Emerald with Matrix (Emerald in Mica Schist)
Beryl (Be3Al2Si6O18) with Chromium/Vanadium impurities
mineral
Anthracite Coal
Anthracite (Carbon-based organic sedimentary rock exposed to metamorphic heat/pressure; Chemical composition is approximately 86%–98% Carbon)
metamorphic
Clear Quartz (Rock Crystal)
Silicon Dioxide (SiO2)
mineral
Tiger's Eye (commonly referred to as Blue/Gold Tiger's Eye)
Tiger's Eye is a variety of Chalcedony (cryptocrystalline quartz), SiO2, exhibiting chatoyancy. The blue variety is often called Hawk's Eye.
Metamorphic Rock (formed from a fibrous crocidolite asbestos)
Jasper Breccia
Silicon Dioxide (SiO2) with impurities
sedimentary
Rhodonite
Rhodonite (Mn,Fe,Mg,Ca)SiO3
mineral
Yellow Calcite
Calcium Carbonate (CaCO3)
mineral
Carnelian and White Quartz Bracelet
Silicon Dioxide (SiO2) - specifically Carnelian (Chalcedony) and Rock Crystal/Snow Quartz
mineral
Citrine
Silicon Dioxide (SiO2)
mineral
Quartz / Citrine Quartz
Silicon Dioxide (SiO2)
mineral
Chrysocolla in Matrix
Hydrated copper silicate - (Cu,Al)2H2Si2O5(OH)4·nH2O
mineral
Healer's Gold (Pyrite and Magnetite in Schist)
Magnetite (Fe3O4) and Pyrite (FeS2) in Mica Schist
metamorphic
Labradorite (tumbled)
Labradorite (a plagioclase feldspar mineral between anorthite and albite; chemical formula: (Ca,Na)(Si,Al)4O8)
Mineral
Quartz (Iron-Stained)
Silicon Dioxide (SiO2)
mineral
Turquoise in Matrix
Hydrous phosphate of copper and aluminium, CuAl6(PO4)4(OH)8·4H2O
mineral
Smoky Quartz
Silicon Dioxide (SiO2)
mineral
Blue Celestite (Celestine)
Strontium sulfate (SrSO4)
mineral
Peridot
Olivine (Magnesium Iron Silicate - (Mg, Fe)2SiO4)
mineral
Red Jasper
Jasper (Silicon Dioxide with Hematite inclusions), SiO2
sedimentary
Conglomerate
Conglomerate (a clastic sedimentary rock)
Sedimentary Rock
Tektite (Indochinite)
Tektite (High-silica natural glass)
igneous
Milky Quartz
Quartz (Silicon Dioxide - SiO2)
mineral
Yellow Jasper (Chert variant)
Silicon Dioxide (SiO2) with iron oxide inclusions
sedimentary
Amethyst (Raw Quartz)
Silicon Dioxide (SiO2) with iron impurities
mineral
Agate (Crazy Lace or Eye Agate)
Silicon Dioxide (SiO2)
mineral
Amazonite
KAlSi3O8 (Potassium aluminum silicate - blue-green variety of Microcline)
mineral