Obsidian (likely Golden Sheen Obsidian or Rainbow Obsidian, given the subtle sheen visible on some beads)
Obsidian (volcanic glass, predominantly SiO2 with various impurities)
Igneous
Category
Sedimentary Rock (Possibly Composed Of Various Minerals)
Browse sedimentary rock (possibly composed of various minerals) specimens identified by the Rock Identifier community.
Granite Pebble
Granite (composed primarily of Quartz SiO2, Feldspar KAlSi3O8, and Mica)
igneous
Sandstone
Arenite (SiO2 primarily)
sedimentary
Granite
Granite
Igneous
Lapis Lazuli
Lapis Lazuli (a rock type, not a single mineral, composed primarily of lazurite, calcite, and pyrite)
Mineral, part of a rock
Silver (S925)
Native Silver (Ag)
mineral
Oolitic Limestone (Oolite)
Oolitic Limestone (primarily Calcium Carbonate, CaCO3)
sedimentary
Sandstone (Ferruginous)
Clastic Sedimentary Rock (Litharenite)
sedimentary
Sandstone
Clastic sedimentary rock (primarily SiO2)
sedimentary
Sandstone
Arenite (SiO2 primarily)
sedimentary
Yellow Jasper
Jasper (Silicon Dioxide with Iron Oxide impurities, SiO2)
sedimentary
Chert (specifically Blue Chert/Flint)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
sedimentary
Schist
Mica Schist (contains muscovite/biotite and quartz)
metamorphic
Sandstone (Calcareous Sandstone)
Calcareous Sandstone (primarily SiO2 with CaCO3 cement)
sedimentary
Quartzite
Quartzite (primarily SiO2)
metamorphic
Hawk's Eye (Blue Tiger's Eye)
Quartz (fibrous crocidolite variety)
Mineral
Sandstone (Water-worn Pebble)
Clastic Sedimentary Rock (primarily SiO2)
sedimentary
Chert Breccia (Yellow Jasper)
Silicon Dioxide (SiO2) - Brecciated Chert
sedimentary
Sandstone
Arenite (primarily SiO2)
sedimentary
Brown Jasper (Likely)
Jasper (Cryptocrystalline Silicon Dioxide - SiO2)
Mineral
Granite Pebble
Granite (composition of Quartz, Alkali Feldspar, and Plagioclase)
igneous
Sandstone (Ferruginous)
Arenite (SiO2 with Fe2O3 inclusions)
sedimentary
Basalt with Scoria
Amygdaloidal Basalt / Vesicular Basalt
igneous
Dendritic Jasper
Silicon Dioxide (SiO2) with Manganese/Iron oxide inclusions
sedimentary
Sandstone (with potential iron-oxide weathering)
Arenite (SiO2 based)
sedimentary
Howlite
Calcium borosilicate hydroxide (Ca2B5SiO9(OH)5)
mineral
Sandstone
Arenite (SiO2 based with quartz grains)
sedimentary
Serpentinite
Serpentinite (group of hydrous magnesium iron phyllosilicates)
metamorphic
Ruby in Zoisite with Hornblende
Anyolite (Ruby: Al2O3, Zoisite: Ca2Al3(SiO4)3(OH))
metamorphic
Serpentinite
Serpentinite (Mg,Fe,Ni,Al,Zn,Mn)2-3(Si,Al,Fe)2O5(OH)4
metamorphic
Cullet (Slag Glass)
Amorphous Silica (SiO2) with various metal oxide colorants
mineraloid / anthropogenic
Sandstone (likely with Quartz Veining)
Arenite (primarily SiO2)
sedimentary
Sandstone (with minor quartz and possible clay components)
Clastic Sedimentary Rock (SiO2 dominated)
sedimentary
Granodiorite
Granodiorite (intermediate intrusive igneous rock)
igneous
Turquoise
Hydrated phosphate of copper and aluminum (CuAl6(PO4)4(OH)8·4H2O)
mineral
Red Jasper (River Polished)
Jasper (Silicon Dioxide, SiO2)
sedimentary/mineral
Ironstone Concretion
Siderite or Ferruginous Concretion (FeCO3 or Iron Oxides)
sedimentary
Sandstone (Ferruginous)
Clastic Sedimentary Rock (SiO2 with FeO/Fe2O3)
sedimentary
Sandstone (Greywacke)
Arenite / Clastic Sedimentary Rock
sedimentary
Smoky Quartz
Smoky Quartz (SiO2: Silicon Dioxide)
mineral
Granite (likely a river or beach pebble)
Granite (a felsic intrusive igneous rock primarily composed of quartz, feldspar, and mica)
Igneous
Jasper (Yellow/Brown variety)
Silicon Dioxide (SiO2) with iron oxide impurities
sedimentary