Gneiss
Gneiss (High-grade regional metamorphic rock)
Category
Browse sedimentary or igneous (secondary formation) specimens identified by the Rock Identifier community.
Gneiss
Gneiss (High-grade regional metamorphic rock)
Leopard Skin Jasper
Silicon Dioxide (SiO2) with impurities
Common Opal in Host Rock
Hydrated Silica (SiO2·nH2O)
Riverstone Quartzite (Water-worn Siltstone/Quartzite)
Metamorphosed Quartz-rich Arenite (SiO2)
Bumblebee Jasper
Calcite with Arsenic and Manganese oxides (technically a volcanic rock)
Greenstone / Diabase Porphyry
Porphyritic Diabase (Micro-gabbro)
Geode (Unopened)
Silica Concretion / Geode (Formula: SiO2 for quartz internal contents)
Galena
Galena (Lead Sulfide), PbS
Quartzite
Metamorphosed Quartz Sandstone (SiO2)
Quartzite
Quartzite (primarily SiO2)
Milky Quartz
Silicon Dioxide (SiO2)
Gneiss (specifically Micaceous Gneiss)
Gneiss (High-grade Regional Metamorphic Rock)
Banded Agate (Gray/Blue Agate)
Agate (Silicon Dioxide, SiO2)
Moss Agate
Silicon Dioxide (SiO2) with Chlorite/Oxide inclusions
Serpentinite
Serpentinite (composed mainly of Group: Serpentine; (Mg,Fe,Ni,Al,Zn,Mn)2-3(Si,Al,Fe)2O5(OH)4)
Quartzite Pebble
Quartzite (primarily SiO2)
Concrete / Anthropogenic Conglomerate
Man-made composite material (Portland cement, aggregate, and water)
Turquoise and Spiny Oyster (Heishi style beads)
Turquoise (CuAl6(PO4)4(OH)8·4H2O) and Spondylus (Spiny Oyster shell)
Gold
Native Gold (Au)
Chrysocolla on Matrix
Hydrated copper phyllosilicate (Cu,Al)2H2Si2O5(OH)4·nH2O
Gold Nugget
Native Gold (Au)
Green Quartz (Prasiolite)
Silicon Dioxide (SiO2) with trace impurities
Ruby
Corundum (Al2O3 with Chromium impurities)
Azurite with Malachite
Azurite: Cu3(CO3)2(OH)2 / Malachite: Cu2CO3(OH)2
Quartz (Rose or Milky variety fragment)
Silicon Dioxide (SiO2)
Azurite and Malachite on Matrix
Azurite: Cu3(CO3)2(OH)2; Malachite: Cu2CO3(OH)2
Gold
Native Gold (Au)
Dendritic Agate or Spotted Quartzite
Silicon Dioxide (SiO2) with inclusions
Milky Quartz with Iron Staining
Silicon Dioxide (SiO2)
Azurite-Malachite with Limonite
Cu3(CO3)2(OH)2 (Azurite) / Cu2CO3(OH)2 (Malachite)
Dyed Agate
Silicon Dioxide (SiO2) with synthetic dyes
Milky Quartz with Iron Staining
Silicon Dioxide (SiO2)
Fossilized Gastropod (Snail)
Class Gastropoda (internal mold or 'steinkern')
Ruby
Corundum (Al₂O₃) with Chromium (Cr)
Clear Quartz
Silicon Dioxide (SiO2)
Pyrite
Iron Sulfide (FeS2)
Quartz (Milky Quartz)
Silicon Dioxide (SiO2)
Pyrite
Iron Sulfide (FeS2)
Clear Quartz
Silicon Dioxide (SiO2)
Milky Quartz with Iron Staining
Quartz (Silicon Dioxide, SiO2)
White Agate (Chalcedony)
Chalcedony (SiO2)
Carnelian
Carnelian (Silicon Dioxide, SiO2)