Coquina
Bioclastic Limestone (composed primarily of CaCO3)
Category
Browse man made object (coin) specimens identified by the Rock Identifier community.
Coquina
Bioclastic Limestone (composed primarily of CaCO3)
Lapis Lazuli
A metamorphic rock primarily composed of lazurite (Na,Ca)8[(S,SO4,Cl)2|(Al6Si6O24)], calcite (CaCO3), and pyrite (FeS2).
Obsidian
Volcanic glass (SiO2 - Silicon Dioxide)
Orange Calcite
Calcium Carbonate (CaCO3)
Fluorite
Calcium Fluoride (CaF2)
Engineered Quartz Stone
Agglomerated Quartz (SiO2 + Polymer Resin)
Blue Sphalerite (likely dyed or treated Druzy Quartz/Agate)
Zinc Sulfide (ZnS) or Silicon Dioxide (SiO2) with trade-name enhancement
Petrified Wood (Jet or Coalified Wood appearance)
Silicified wood (principally SiO2) or Carbonized Wood
Petrified Wood
Silicified Wood (primarily Quartz/Chalcedony, formula: SiO2)
Banded Calcite (often sold as Caribbean Calcite or Mexican Onyx)
Calcium Carbonate (CaCO3)
Tiger's Eye
Pseudomorph of quartz after crocidolite (SiO2)
Nephrite Jade
Nephrite
Chrysoprase
Silicon dioxide (SiO2) with nickel impurities
Amazonite
Amazonite (KAlSi3O8 - Microcline)
Diamond
Diamond (pure Carbon, C)
Watermelon Tourmaline
Elbaite - Na(Li1.5Al1.5)Al6(Si6O18)(BO3)3(OH)3OH
Obsidian
Volcanic Glass (Amorphous Silicon Dioxide)
Fossilized Coral (Coquina/Limestone)
Cnidaria Anthozoa (Fossilized)
Coquina
Bioclastic Limestone
White Marble
Recrystallized Calcite (CaCO3)
White Marble
Calcite-rich Metasomatized Carbonate (CaCO3)
Lepidolite with Quartz
K(Li,Al)3(Al,Si,Rb)4O10(F,OH)2
Granite
Plutonic Igneous Rock (composed typically of SiO2, Al2O3, K2O, Na2O, CaO)
Stichtite in Serpentine (Atlantisite)
Mg6Cr2CO3(OH)16·4H2O (Stichtite) within Mg3Si2O5(OH)4 (Serpentine)
Limestone
Calcium Carbonate (CaCO3)
Sandstone (Pet Rock)
Clastic sedimentary rock (primarily SiO2)
Green Fluorite
Calcium Fluoride (CaF2)
Fluorite
Calcium Fluoride (CaF2)
Fluorite (specifically Rainbow Fluorite or Purple Fluorite)
Calcium Fluoride (CaF2)
Lepidolite
Lepidolite (K(Li,Al)3(Al,Si,Rb)4O10(F,OH)2)
Amazonite
Amazonite (KAlSi3O8)
Amazonite
Potassium Feldspar (Microcline) - K(AlSi3O8)
Amazonite
K(AlSi3O8) - Microcline (Var. Amazonite)
Jasper
Jasper (Silicon Dioxide, SiO2)
Jasper
Silicon Dioxide (SiO2)
Gold (Processed)
Gold (Au)
Jade (likely Nephrite or Jadeite)
Nephrite (a variety of actinolite, Ca2(Mg,Fe)5Si8O22(OH)2) or Jadeite (NaAlSi2O6)
Granite
Phaneritic Igneous Rock (composed primarily of Quartz, Alkali Feldspar, and Plagioclase)
Diabase (Greenstone)
Diabase (also known as Dolerite)
Chert (specifically Tan/Gray Chert)
Microcrystalline quartz (SiO2)
Quartz
Silicon Dioxide (SiO₂)
Milky Quartz with Mineral Inclusions
Quartz (Silicon Dioxide, SiO2)