Banded River Rock / Gneiss (highly weathered)
Gneiss
Category
Browse igneous or sedimentary (anthropogenic modification) specimens identified by the Rock Identifier community.
Banded River Rock / Gneiss (highly weathered)
Gneiss
Sandstone (Arkose)
Arkose Sandstone (SiO2 with KAlSi3O8)
Agate
Silicon Dioxide (Chalcedony), SiO2
Nile Agate
Silicon Dioxide (SiO2)
Dark Agate / Chalcedony
Microcrystalline Quartz (SiO2)
Cryptocrystalline Quartz (Agate/Chert)
Silicon dioxide (SiO2)
Quartz-rich sandstone or granitic fragment
Likely quartz–feldspar sandstone; exact identification is uncertain from the photograph
Greenstone (Epidosite / Chlorite Schist)
Metabasalt (often contains Epidote Ca2Al2(Fe3+,Al)(SiO4)(Si2O7)O(OH) or Chlorite)
Quartz Pebble
Silicon dioxide (SiO2)
Greenstone / Greenschist
Greenschist facies metamorphic rock
Quartz pebble
Quartz (SiO2)
Dragon Blood Jasper
Epidote with Red Piedmontite (silicate)
Quartz Pebble
Silicon Dioxide (SiO2)
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
Magnetite-rich ironstone (probable magnetite ore)
Magnetite, Fe₃O₄, likely in a fine-grained ironstone matrix
River Rock (Basalt/Greywacke)
Aphanitic Basalt or Lithic Sandstone (Greywacke)
Pyrite
Iron Sulfide (FeS2)
Mixed River Stones and Minerals
Mixed Silica-rich Stones (Quartz, Agate, Jasper, Sandstone, Dalmation Stone)
Sandstone (Ferruginous)
Arenite (primarily SiO2 with Fe2O3 inclusions)
Quartz
Silicon Dioxide (SiO2)
White Quartz
Quartz (Silicon Dioxide, SiO2)
Quartz
Silicon Dioxide (SiO2)
Quartz pebble
Silicon dioxide (SiO2)
Milky Quartz
Silicon Dioxide (SiO2)
Quartz (Milky or White Quartz)
Silicon Dioxide (SiO2)
Quartz
Silicon Dioxide (SiO2)
Quartz (Yellow / Citrine Quartz Pebble)
Silicon Dioxide (SiO2)
Quartz Pebble
Silicon Dioxide (SiO2)
Banded Gneiss
Gneiss (Felsic to Mafic Metamorphic Rock)
Pyrite (Fool's Gold)
Iron Disulfide (FeS2)
Pyrite with Quartz
Iron Sulfide (FeS2) with Silicon Dioxide (SiO2)
Quartz
Silicon Dioxide (SiO2)
Iron-stained Quartz
Silicon Dioxide (SiO2) with Hematite/Limonite inclusions
Fuchsite Schist with Quartz
Chromian Muscovite [K(Al,Cr)2(AlSi3O10)(OH)2] Schist
Quartz (Clear Quartz)
Silicon Dioxide (SiO2)
Amphibolite / Biotite Schist
Amphibolite (rich in Hornblende and Plagioclase feldspar)
Gneiss
Gneiss
Quartz Pebble
Silicon Dioxide (SiO2)
Gneiss
Gneiss (High-grade Regional Metamorphic Rock)
Gneiss (Granitic Gneiss)
Gneiss (composed primarily of Quartz, Feldspar, and Mica)
Pyrite
Iron Disulfide (FeS2)
Quartz (Clear Quartz)
Silicon Dioxide (SiO2)