Sandstone
Clastic sedimentary rock (primarily SiO2)
sedimentary
Category
Mineralogical
Browse mineralogical specimens identified by the Rock Identifier community.
Gossan with Copper Carbonate (Chrysocolla/Malachite)
Ferruginous Oxide (Gossan) with Cu2CO3(OH)2 (Malachite) or (Cu,Al)2H2Si2O5(OH)4 (Chrysocolla)
Mineral/Sedimentary Interface
Snowflake Obsidian
Volcanic Glass with Cristobalite inclusions
igneous
Diorite Gneiss
Foliated Diorite Gneiss
metamorphic
Granite
Phaneritic Igneous Rock (composed primarily of Quartz, Alkali Feldspar, and Plagioclase)
igneous
Gneiss
High-grade Metamorphic Gneiss
metamorphic
Quartzite
Metamorphosed Quartz Sandstone (SiO2)
metamorphic
Granite
Granite (Felsic Plutonic Rock)
igneous
Limonite (Ironstone Concretion)
Limonite (Hydrous Ferric Oxides mixed with Goethite)
sedimentary
Pink Granite
Phaneritic Felsic Igneous Rock
igneous
Optical Calcite (Iceland Spar)
Calcite (Calcium Carbonate, CaCO3)
mineral
Gabbro
Gabbro (composed mainly of calcium-rich plagioclase feldspar and pyroxene)
igneous
Crushed Stone (Gravel/Aggregates)
Crushed rock aggregate (varied composition including Granite, Limestone, and Quartz)
sedimentary and igneous (mixed)
Quartzite
Quartzite (primarily SiO2)
metamorphic
Red Granite
Phaneritic Felsic Intrusive Igneous Rock (primarily K-feldspar, Quartz, and Biotite)
igneous
Red Granite
Phaneritic Plutonic Rock (High Potassium Feldspar)
igneous
Granite
Granite (Phaneritic igneous rock)
igneous
Granite
Phaneritic Igneous Rock (composed primarily of Quartz SiO2, Alkali Feldspar, and Plagioclase)
igneous
Quartz (Iron-stained)
Silicon Dioxide (SiO2)
mineral
Banded Gneiss (with Quartz Vein)
Gneiss (Metamorphic rock of varying mineralogy)
metamorphic
Sandstone (Quartzose Sandstone)
Arenite (primarily SiO2 with minor Fe2O3)
sedimentary
Hypersthene
Enstatite (Hypersthene variety), (Mg,Fe)SiO3
mineral
Charoite
Charoite (K(Ca,Na)2Si4O10(OH,F)·nH2O)
metamorphic
Mica Schist
Mica Schist (primarily Muscovite or Biotite)
metamorphic
Quartzite
Quartzite (SiO2)
metamorphic
Gneiss (specifically a granitic gneiss cobble)
Gneiss (high-grade regional metamorphic rock)
metamorphic
Chert (Green River Chert)
Microcrystalline Quartz (SiO2)
sedimentary
Granite
Intrusive Phaneritic Felsic Igneous Rock
igneous
Dendritic Agate (or Dendritic Opal)
SiO2 (for Agate), SiO2·nH2O (for Opal)
Mineral
Mica Schist (with Golden/Biotite inclusions)
K(Mg,Fe)3AlSi3O10(F,OH)2 (Biotite), KAl2(AlSi3O10)(F,OH)2 (Muscovite)
metamorphic
Granite (Dioritic or Hornblende-rich)
Phaneritic Plutonic Felsic to Intermediate Igneous Rock
igneous
Hypersthene
(Mg,Fe)SiO3 - Enstatite-Ferrosilite series
mineral
Chert (specifically Silex or Flint)
Microcrystalline Quartz (SiO2)
sedimentary
Granite
Granite
igneous
Drill Core Sample
Cylindrical Rock Core (Specific mineralogy varies by extraction site)
Metamorphic (Likely Gneiss or Schist based on texture)
Rose Quartz
Silicon Dioxide (SiO2) with trace amounts of titanium, iron, or manganese
mineral
Ocean Jasper (Orbicular Jasper)
Silica (SiO2) with varied mineral inclusions
mineralogical specimen
Schist
Schist (various mineralogical compositions including mica, chlorite, talc, etc.)
Metamorphic
Banded River Rock / Gneiss (highly weathered)
Gneiss
Metamorphic rock
Prasiolite and Quartz Crystal Cluster
Quartz (SiO2); Prasiolite is a variety of Quartz
mineral
Gneiss
Gneiss (a type of metamorphic rock)
Metamorphic Rock
Banded Gneiss
Gneiss (Metamorphic rock of variable mineralogy, often quartz-feldspar base)
metamorphic