Sedimentary Rock (Metamorphosed)

Marble

Metamorphosed Limestone (main mineral: Calcite, CaCO3)

Shale or Slaty Mudstone

Argillaceous sedimentary rock

Biotite-bearing granite or granitic gneiss

Quartz–feldspar–biotite rock; commonly granite (quartz + K-feldspar/plagioclase + biotite)

Pink Marble (Quartzite or Calcite mix)

Metamorphosed Limestone / Quartzite (CaCO3 or SiO2 with iron impurities)

Chert (specifically Novaculite)

Microcrystalline Quartz (SiO2)

Weathered quartz-rich sandstone, possibly iron-stained quartzite

Quartz sandstone (quartz arenite), SiO₂-rich; exact identification requires hardness and texture tests

Biotite-bearing granite or granitic gneiss

Quartz–feldspar–biotite assemblage; possibly metamorphosed granite (gneiss)

Weathered sandstone or quartzite fragment

Quartz-rich sandstone; possibly weakly metamorphosed quartzite

Shale

Argillite / Shale

Quartzite with Iron Banding

Metamorphosed Quartz-rich Sandstone (SiO2 with Fe2O3 inclusions)

Weathered greenstone pebble

Metamorphosed mafic rock, commonly metabasalt or greenschist (exact identification requires testing)

Unakite

Epidote-Feldspar rock (specifically, a variety of granite)

Banded Iron Formation

Banded Iron Formation (BIF)

Granite or granitic gneiss

Felsic granitoid, chiefly quartz, feldspar, and mica; possibly weakly foliated gneiss

Quartzite

Quartzite (primarily SiO2)

Demantoid Garnet on Matrix

Demantoid (variety of Andradite Garnet) - Ca3(Fe3+)2(SiO4)3

Shale / Mudstone

Laminated Mudrock (Siliciclastic Sedimentary Rock)

Shale (Beach-worn)

Laminated Pelite (primarily clay minerals and quartz)

Quartzite River Rock with Dendrites

Metamorphosed Quartz-rich Sandstone with Manganese Oxide (MnO2) inclusions

Shale

Fissile Mudstone (primarily composed of phyllosilicate minerals like kaolinite, montmorillonite, and illite)

Fossilized Shell Impression / Siltstone Fossil

Bivalvia / Brachiopoda mold in Siltstone

Marble

Metamorphosed Limestone (primarily calcite CaCO3 or dolomite CaMg(CO3)2)

Quartzite

Quartzite (primarily SiO2)

Quartz-rich sandstone or quartzite fragment

Quartz sandstone; possibly weakly metamorphosed quartzite (SiO₂-dominant)

Likely weathered sandstone or quartzite

Quartz-rich sandstone; possibly metamorphosed to quartzite (SiO₂-dominant)

Sandstone or Siltstone

Arenite (if sandstone)

Sandstone or Mudstone

Sedimentary Rock

Shale

Shale (Fine-grained clastic sedimentary rock)

Shale

Argillaceous sedimentary rock

Fossiliferous Sedimentary Rock

Sedimentary limestone with invertebrate fossil imprint

Shale

Lutaceous sedimentary rock

Shale

Shale (clastic sedimentary rock composed of silt and clay-sized particles)

Shale

Fissile mudstone (Shale)

Quartzite

Quartzite

Sandstone

Arenite

Phyllite (possibly low-grade greenish slate)

Foliated metamorphic rock composed mainly of very fine-grained quartz, mica, and chlorite; approximate composition varies and has no single fixed chemical formula

Shale fragment

Shale (clay mineral rich sedimentary rock)

Shale / Mudstone

Sedimentary rock (Claystone / Mudstone / Shale)

Brown Sandstone (River Rock)

Arenite

Shale

Clastic Sedimentary Rock

Sandstone

Clastic sedimentary rock (primarily SiO2)

Shale

Shale (claystone/mudstone)