Not A Rock Or Mineral

Serpentinite

Serpentinite (composed primarily of Serpentine group minerals (Mg,Fe,Ni,Al,Zn,Mn)2-3(Si,Al,Fe)2O5(OH)4)

Mixed Rock Collection (Pebbles and Stones)

Various geological specimens

Quartzite with Schist layers

Metamorphosed Quartz-rich Rock (Mixed Schist/Quartzite)

Quartz (Clear/Smoky Geode fragment)

Silicon Dioxide (SiO2)

Sandstone with Manganese Dendrites

Clastic Sedimentary Rock (SiO2 based with MnO2 inclusions)

Amygdaloidal Basalt

Vesicular basalt with mineral infillings

Quartz Vein in Metamorphic Rock

Quartz-veined Schist or Gneiss

River Pebble (Siltstone / Fine-grained Sandstone)

Sedimentary Pebble (Siliclastic)

Quartz Geode

Silicon dioxide (SiO2)

Sandstone

Arenite (SiO2 dominant)

Quartz Cluster on Matrix

Silicon Dioxide (SiO2)

Granite

Phaneritic plutonic rock (primarily Quartz, Feldspar, and Mica)

Vuggy Quartz on Matrix

Crystalline Silicon Dioxide (SiO2)

Granite

Felsic intrusive igneous rock

Granite

Felsic intrusive igneous rock

Copper Ore (Malachite and Azurite stained rock)

Copper-bearing rock with secondary copper carbonates

Sandstone

Arenite (primarily SiO2)

River Stone (likely Basalt or Greywacke)

Basalt with mineral veining

Small brown mineral or rock fragment

Undetermined; the image does not show enough diagnostic detail for reliable identification

Granite

Intrusive Igneous Rock (composed primarily of quartz, alkali feldspar, and plagioclase)

Granite Pebble (Pegmatitic Quartz-Feldspar River Rock)

Granite / Quartz-Feldspar-Mica Aggregate

Greenish metamorphic rock (possibly chlorite schist)

Chlorite-rich schist; exact identification is uncertain from the image

Unidentified dark mineral/rock fragment

Indeterminate; appearance may fit a sulfide-bearing rock or iron-rich mineral

Quartz-Veined Slate or Greenstone

Metamorphic rock with quartz vein (SiO2)

Wishing Stone (Quartz Vein in Greywacke / Basalt)

Quartz vein in host rock (e.g. Meta-basalt or Greywacke)

Quartz Geode

Quartz (Silicon Dioxide, SiO2)

Quartzite Pebble

Quartzite (mostly SiO2)

Milky Quartz with Chlorite Schist Inclusions

Quartz (SiO2) with Chlorite Group silicates (typically (Mg,Fe)3(Si,Al)4O10(OH)2)

Granite Pebble with Quartz Vein

Granite (Plutonic Igneous Rock) with Quartz (SiO2)

Geode Nodule Fragment

Quartz / Chalcedony Nodule

Granite fragment

Granite, a coarse-grained felsic intrusive igneous rock composed mainly of quartz, feldspar, and mica

Gossan (with Limonite/Hematite coating)

Ferruginous Gossan (Fe2O3·nH2O / Fe2O3)

Generic Pebble

Lithic Fragment

Schist (likely Mica Schist)

Mica Schist

Likely bituminous coal

Coal, predominantly carbon-rich organic matter; exact rank cannot be confirmed from the image

Geode

Quartz / Chalcedony nodule

Weathered granite boulder

Granite, a quartz–feldspar-rich intrusive igneous rock

Dark igneous rock, likely basalt or diabase, with a second purplish specimen

Basalt/diabase; exact identification is uncertain from the photograph

Red Sandstone

Arenite (primarily quartz with iron oxide cement)

Sandstone

Sedimentary Rock

Xenolith in Basalt

Mafic Igneous Rock with Felsic Inclusion

Polished unakite pebble

Unakite: epidote–feldspar (commonly pink K-feldspar and green epidote), with quartz