Red Jasper
SiO2 (Silicon Dioxide with Iron inclusions)
Category
Browse organic gemstone (often associated with sedimentary sequences) specimens identified by the Rock Identifier community.
Red Jasper
SiO2 (Silicon Dioxide with Iron inclusions)
Agate
Silica (Chalcedony), SiO2
Petrified Wood
Silicified Wood (SiO2 permineralization)
Chert (Nodular or Massive Variety)
Cryptocrystalline Quartz (SiO2)
Fluorite
Calcium Fluoride (CaF2)
Red Jasper
Silicon Dioxide (Microcrystalline Quartz, SiO2)
Rhodonite
Rhodonite (Mn,Fe,Mg,Ca)SiO3
Black Limestone
Bituminous Limestone (Calcium Carbonate - CaCO3)
Chrysocolla
Chrysocolla (Cu2–xAlx(H2–xSi2O5)(OH)4·nH2O)
Amber with dark mineral/organic inclusions
Fossilized plant resin (amber; chiefly polymerized diterpenoid resin)
Tumbled yellow chalcedony (likely citrine or yellow jasper)
Cryptocrystalline quartz, SiO₂; exact identification requires testing
Prehnite
Prehnite (Ca2Al(AlSi3O10)(OH)2)
Prehnite
Prehnite (Ca2Al(AlSi3O10)(OH)2)
Chert (variations include Flint or Jasper)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Petrified Wood with Lichen
Silicified Wood (SiO2) colonized by crustose lichens
Limestone
Calcium Carbonate (CaCO3)
Fluorite
Calcium Fluoride (CaF2)
Chert / Flint
Silicon Dioxide (SiO₂)
Chert (specifically Jasper or Flint variety)
Cryptocrystalline Quartz (SiO2)
Petrified Wood
Silicified Wood (primarily Quartz/Chalcedony, SiO2)
Serpentinite
Serpentinite (complex silicate mineral group (Mg,Fe)3Si2O5(OH)4)
Epidote
Ca2(Al,Fe)3(SiO4)3(OH)
Chert (varieties include Flint or Jasper)
Chert (cryptocrystalline quartz; SiO₂)
Polished brecciated jasper or agate
Microcrystalline quartz (chalcedony), SiO₂, with iron-oxide and possibly carbonate inclusions
Green Jasper
Microcrystalline Quartz (SiO2)
Fossiliferous Sandstone
Sedimentary rock containing invertebrate fossils
Orange Calcite
Calcium Carbonate (CaCO3)
Petrified Wood
Silicified Wood (SiO2)
Chert (Yellow Jasper/Flint)
Silicon Dioxide (SiO2)
Sugilite
KNa2(Fe,Mn,Al)2Li3Si12O30
Sodalite
Sodalite (Na8(Al6Si6O24)Cl2)
Fluorite
Calcium Fluoride (CaF2)
Chert (Flint)
Silicon Dioxide (SiO2)
Epidote
Epidote (Ca2(Al2,Fe3+)(SiO4)(Si2O7)O(OH))
Gneiss
Gneiss (High-grade regional metamorphic rock)
Sodalite
Na8Al6Si6O24Cl2
Red Jasper
Microcrystalline Quartz (SiO2)
Emerald
Beryl (Be3Al2Si6O18 with Chromium/Vanadium impurities)
Chert (Jasper/Flint variety)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Rhodonite
Manganese Silicate (Mn,Fe,Mg,Ca)SiO3
Jasper
Silicon dioxide (Microcrystalline Quartz, SiO2)
Howlite
Howlite (Calcium borosilicate hydroxide, Ca2B5SiO9(OH)5)