Sandstone
Sandstone (composed primarily of sand-sized minerals or rock grains)
Category
Browse sedimentary or metamorphic (base substrate) specimens identified by the Rock Identifier community.
Sandstone
Sandstone (composed primarily of sand-sized minerals or rock grains)
White Quartz Sphere
Silicon Dioxide (SiO2)
Dalmatian Jasper
Dalmatian Stone (Arfvedsonite/Albite Microquartz)
Tree Agate
Silicon Dioxide with Chlorite inclusions (SiO2)
Tiger's Eye
Pseudomorph of Quartz after Crocidolite (SiO2 with iron inclusions)
Green Aventurine
Silicon Dioxide (SiO2) with Chromium-rich Fuchsite mica
Orbicular Granite (specifically Mustard or Yellow Tonalite/Granodiorite)
Orbicular Quartz Diorite / Tonalite
Porphyry
Porphyritic Basalt or Porphyritic Andesite
Labradorite (Feldspar)
Labradorite, (Ca,Na)(Al,Si)4O8
Bloodstone (Heliotrope)
Silicon Dioxide (SiO2) with iron silicate and iron oxide inclusions
Bloodstone (Heliotrope)
Silicon dioxide (SiO2) with iron oxide inclusions
Peridotite
Ultramafic intrusive rock (Peridotite)
Clear Quartz
Quartz (Silicon Dioxide, SiO2)
Pink Granite
Phaneritic Felsic Intrusive Igneous Rock
Aqua Aura Quartz
Silicon Dioxide (SiO2) bonded with Gold (Au)
Lepidolite
K(Li,Al)3(Al,Si,Rb)4O10(F,OH)2
Greenstone / Chert
Cryptocrystalline Quartz (SiO2) or Altered Basalt
Citrine
Silicon Dioxide (SiO2) - Macrocrystalline Quartz variety
River Stone (possibly Gneiss)
Metamorphic Gneiss
Citrine Quartz Geode
Silicon Dioxide (SiO2) with iron impurities
Aura Rose Quartz
SiO2 (Silicon Dioxide with Titanium/Gold coating)
Clear Quartz Cluster
Silicon Dioxide (SiO2)
Pink Granite
Phaneritic Igneous Rock (high K-feldspar content)
Granite
Granite (a phaneritic intrusive igneous rock)
Green Apophyllite on Stilbite
Fluorapophyllite-(K) [(KCa4Si8O20F)·8H2O] and Stilbite [NaCa4(Si27Al9)O72·28H2O]
Pyrite
Pyrite (FeS2)
Quartz (Water-worn Pebble)
Quartz (Silicon Dioxide, SiO2)
Mixed Quartz and River Pebbles (Stone Collection)
Mixed assortment containing mainly Silicon Dioxide (SiO2)
Terracotta (Man-made ceramic brick fragment)
Baked clay / High-iron ceramic (Silicate-based ceramic)
Basalt with Caliche
Extrusive Mafic Igneous Rock with Secondary Carbonate Crust
Chrysocolla in Jasper (Chryso-Jasper)
Cu2-xAlx(H2-xSi2O5)(OH)4·n H2O (Chrysocolla) + SiO2 (Jasper)
Blue Quartzite
Quartzite (specifically a variety enriched with blue-coloring minerals)
Serpentinite (Serpentine Rock)
Serpentinite is a rock composed of one or more serpentine group minerals, chiefly antigorite, chrysotile, and lizardite, with the general formula (Mg,Fe)3Si2O5(OH)4. Often includes other minerals like magnetite, talc, and chromite.
Green Tree Agate
Agate (SiO2)
Snowflake Obsidian
Spherulitic Volcanic Glass (SiO2 + impurities)
Tree Agate
Dendritic Agate (Silicon Dioxide, SiO2)
Heat-Treated Citrine (Amethyst Cathedral with Agate inclusions)
Silicon Dioxide (SiO2) with iron impurities
Bloodstone (Heliotrope)
Silicon Dioxide (SiO2) with Iron Oxide inclusions
Snowflake Obsidian
Vitreous volcanic silicate rock (SiO2) with Spherulite inclusions
Obsidian / Chert (Arrowhead Artifact)
Obsidian (volcanic glass, SiO2 with impurities)
Dzi Bead (Agate)
Chalcedony (cryptocrystalline variety of Quartz), SiO2
K2 Jasper
Azurite in Granite