Sandstone
Arenite
Category
Browse not a natural rock (man made composite) specimens identified by the Rock Identifier community.
Sandstone
Arenite
Pearl
Calcium Carbonate (CaCO3) - Aragonite/Calcite
Dyed Agate
Silicon Dioxide with artificial pigment (SiO2)
Amethyst (Tumbled)
Silicon Dioxide (SiO2) with iron impurities
Diamond
Carbon (C)
Chert
Chert (SiO2)
Smoky Quartz
Silicon Dioxide (SiO2)
Banded Chert
Microcrystalline Quartz (SiO2)
Diamond (or Cubic Zirconia)
Carbon (C) / Cubic Zirconium Dioxide (ZrO2)
Quartz (Smoky/Grey Variety)
Silicon Dioxide (SiO2)
Dyed Dragon Vein Agate
Silicon Dioxide (SiO2) with artificial dye
Milky and Smoky Quartz Cobble
Silicon Dioxide (SiO2)
Smoky Quartz
Silicon Dioxide (SiO2)
Engineer Quartz/Quartzite
SiO2 (Silicon Dioxide with binders)
Granite
Granitoid
Citrine (likely Heat-Treated Amethyst)
Silicon Dioxide (SiO2)
Quartz (Smoky Quartz variant)
Silicon Dioxide (SiO2)
Smoky Quartz
Silicon Dioxide (SiO2)
Chert (with Limestone matrix)
Silicon dioxide (SiO2)
White Marble
Recrystallized Calcite (CaCO3)
Citrine
Silicon Dioxide (SiO2)
Citrine
Silicon Dioxide (SiO2)
Green Quartz (Prasiolite/Adventurine)
Silicon Dioxide (SiO2) with inclusions
Emerald
Beryl (Be3Al2(SiO3)6) with trace Chromium/Vanadium
Amethyst (Faceted)
Quartz (SiO2) with iron impurities
Amethyst
Quartz (Silicon Dioxide, SiO2) with iron impurities
Fossilized Shell in Limestone
Biogenic Limestone (Calcium Carbonate, CaCO3)
Chert (Jasper variation)
Microcrystalline Quartz (SiO2)
Bornite (Peacock Ore)
Bornite (Cu5FeS4)
Blue Sphalerite (likely dyed or treated Druzy Quartz/Agate)
Zinc Sulfide (ZnS) or Silicon Dioxide (SiO2) with trade-name enhancement
Quartzite
Metamorphic Quartz (SiO2)
Aventurine
Silicon Dioxide (SiO2) with inclusions of Fuchsite
Amethyst
Silicon dioxide (variant with ferric iron impurities), SiO2
Peacock Ore
Bornite (Cu5FeS4) or Chalcopyrite (CuFeS2) with iridescent tarnish
Bornite (Peacock Ore)
Bornite (Cu5FeS4)
Citrine Quartz
Silicon Dioxide (SiO2)
Granite
Granite (Mainly Quartz, Feldspar, and Mica/Amphibole)
Yellow Quartz (Citrine Quartz Pebble)
Silicon Dioxide (SiO2)
Blue Agate (Dyed)
Silicon Dioxide (SiO2) with artificial pigment
Citrine
Citrine (Silicon Dioxide - SiO2)
Diamond
Natural Carbon (C)
Fossilized Coral (Petoskey-style)
Hexagonaria percarinata (Fossilized Rugose Coral)