Granite
Granite (Felsic Plutonic Rock)
Category
Browse organic gemstone (not a rock or mineral) specimens identified by the Rock Identifier community.
Granite
Granite (Felsic Plutonic Rock)
Quartz / Common Opal Transition
Silicon Dioxide (SiO2)
Sandstone (Quartzose)
Arenite (primarily SiO2)
Sandstone
Arenite (primarily SiO2)
Quartz Geode Fragment
Silicon Dioxide (SiO2)
Sandstone (Ferruginous)
Arenite (composed primarily of SiO2 with Fe2O3 staining)
Amethyst
Amethyst (Silicon Dioxide - SiO2 with iron impurities)
Pink Opal
Hydrated Silica (SiO2·nH2O) with Palygorskite inclusions
Banded Gneiss
Gneiss (Metamorphic Rock)
Prehnite
Prehnite (Ca2Al2Si3O10(OH)2)
Magnetite
Magnetite (Fe3O4)
Amazonite
Microcline (variety Amazonite), K(AlSi3O8)
Olivine (Peridot)
Magnesium Iron Silicate ((Mg, Fe)2SiO4)
Quartz (Clear Quartz)
Silicon Dioxide (SiO2)
Chrysocolla
Chrysocolla; (Cu,Al)2H2Si2O5(OH)4·nH2O
Chert (Nodule)
Microcrystalline Quartz (SiO2)
Chert (Jasper/Flint variety)
Microcrystalline quartz (SiO2)
Chert Pebble
Microcrystalline Quartz (SiO2)
Chert (Jasper/Agate variety)
Microcrystalline Quartz (SiO2)
Banded Chert (River Pebble)
Microcrystalline Quartz (SiO2)
Chert (Nodule/Common Chert)
Microcrystalline quartz (SiO2)
Chert (Flint Nodules)
Silicon Dioxide (SiO2)
Chert (Brown Variety)
Microcrystalline quartz (SiO2)
Banded Chert
Silicon Dioxide (SiO2)
Dragon Blood Jasper
Epidote with Red Piedmontite (Chalcedony/Quartz variant)
Chert (specifically Flint or Common Opal)
Silicon Dioxide (SiO2)
Aquamarine
Beryl (Be3Al2Si6O18 with Fe2+ impurities)
Charoite
Charoite, K(Ca,Na)2Si4O10(OH,F)·H2O
Dyed Agate
Silicon Dioxide (SiO2)
Amethyst (Purple), Sulfur (Yellow), and Blue Apatite
SiO2 (Quartz), S (Native Sulfur), Ca5(PO4)3(F,Cl,OH) (Apatite Group)
Sandstone (likely Quartzose)
Sandstone (Principally SiO2)
Quartz Geode
Silicon Dioxide (SiO2) in Host Rock
Blue Sodalite
Sodalite (Na8(Al6Si6O24)Cl2)
Granite Gneiss
Gneiss (High-grade regional metamorphic rock)
Amygdaloidal Basalt with Epidote
Vesicular Basalt with secondary Epidote/Quartz mineral infill
Granite (Pink/Red)
Phaneritic Plutonic Felsic Rock (major minerals: Quartz, Orthoclase Feldspar, Plagioclase Feldspar)
Quartz Druzy Geode
Silicon Dioxide (SiO2)
Tiger's Eye
Pseudomorph of Quartz after Crocidolite (SiO2)
Green Banded Chert (Agate/Jasper)
Silicon Dioxide (SiO2) with trace impurities of Chlorite or Glauconite
Chrysocolla
Chrysocolla, (Cu, Al)2H2Si2O5(OH)4·nH2O
Howlite
Calcium Borosilicate Hydroxide (Ca2B5SiO9(OH)5)
Quartz (Peach/Orange variety)
Silicon Dioxide (SiO2)