Mineral Based Composite

Sandstone

Arenite (mainly SiO2 with varying cements)

Milky Quartz with Talc / Serpentine

Silicon Dioxide (SiO2) with Mg3Si4O10(OH)2

Epidote

{Ca2}{Al2Fe3+}(Si2O7)(SiO4)O(OH)

Granite

Phaneritic plutonic rock (Quartz, Feldspar, Mica)

Quartz (likely Rose Quartz or Milky Quartz based on color)

Quartz (SiO2 - Silicon Dioxide)

Titanium Amethyst Geode

Silicon Dioxide (SiO2) with Titanium/Metal Vapor Deposition Layer

Gneiss (River Cobble)

Gneiss

Granite

Phaneritic Intrusive Igneous Rock (primarily Quartz, Feldspar, and Mica)

Clear Quartz Cluster

Silicon Dioxide (SiO2)

Schist

Mica Schist

Limestone with Fossil Fragment

Sedimentary carbonate rock (CaCO3)

Kaolinite (China Clay)

Kaolinite (Al2Si2O5(OH)4)

Mica Schist

Mica Schist (Schistose metamorphic rock rich in Muscovite/Biotite)

Vesicular Basalt with Pyrite

Basalt (MgFe2+)(Si,Al)2O6 containing FeS2 inclusions

Aura Rose Quartz

SiO2 (Silicon Dioxide with Titanium/Gold coating)

Epidote

Epidote (Ca2(Al2,Fe3+)(SiO4)(Si2O7)O(OH))

Weathered granite (feldspathic, iron-stained granite)

Granite; primarily quartz, potassium feldspar, plagioclase feldspar, and minor mica/amphibole. Exact identification is uncertain from a single photograph.

Biotite Schist

Biotite-rich Schist [K(Mg,Fe)3AlSi3O10(F,OH)2]

Mica-bearing quartz rock (likely pegmatite)

Quartz–feldspar–mica pegmatite; dark mica is probably biotite, possibly muscovite or chlorite

Breccia Pebble

Sedimentary Breccia

Sandstone Pebble

Quartz Sandstone

Sandstone (lithic wacke/conglomerate mix)

Clastic Sedimentary Rock (SiO2 with lithic fragments)

Calcite with Quartz coating

Calcium Carbonate (CaCO3) with Silicon Dioxide (SiO2)

Granodiorite

Granodiorite

Rose Quartz (tumbled)

Rose Quartz (variety of Quartz, chemical formula SiO₂)

Desert Rose (Barite Rose / Gypsum Rose)

Barium Sulfate (BaSO4) or Hydrous Calcium Sulfate (CaSO4%22H2O)

Polymictic breccia, possibly volcanic breccia

Polymictic clastic breccia; likely a matrix-supported breccia containing lithic fragments, quartz, feldspar, and dark mafic minerals

Basalt (Glassy)

Basalt (Aphanitic-Glassy texture)

Porphyritic Basalt

Basalt (Extrusive Igneous Rock)

Limestone Riprap

Sedimentary Calcium Carbonate (CaCO3)

Quartz with Celadonite Inclusion

Silicon Dioxide (SiO2) with green clay mineral inclusions

Breccia

Breccia (Clastic Sedimentary Rock)

Schist

Mica Schist

Sandstone

Arenite (primary component SiO2)

Druzy Quartz on Ironstone

Silicon Dioxide (SiO2) on Limonitic Ironstone

Shark Tooth Fossil

Otodus sp. (possibly Cretalamna)

Jasper (likely Brecciated or Multi-colored)

Jasper (SiO2)

Banded Gneiss

Gneiss (Felsic to Mafic Metamorphic Rock)

Basalt

Mafic volcanic rock (primarily plagioclase feldspar and pyroxene)

Quartz (Milky/Smoky variety on matrix)

Silicon Dioxide (SiO2)

Schist (Micaceous Schist)

Mica Schist

Epidote

Calcium aluminum iron silicate (Ca2(Al, Fe)3(SiO4)3(OH))