Mineral In A Matrix (Likely Quartz Or Feldspar)

Granite

Granite (Felsic Plutonic Rock)

Chert (Beach Pebble)

Silicon Dioxide (SiO2)

Druzy Chalcedony/Quartz on Fluorite core

Silicon Dioxide (SiO2) on Calcium Fluoride (CaF2)

Chert Pebble with Quartz Veins

Microcrystalline Quartz (SiO2)

Quartz Druzy (on Matrix)

Silicon Dioxide (SiO2)

Granodiorite

Granodiorite (containing Plagioclase, Quartz, and Biotite)

Milky Quartz Geode Fragment

Silicon Dioxide (SiO2)

Quartz with Iron Stains

Quartz (SiO2) with iron oxide/hydroxide staining

Gneiss (Banded Gneiss)

Gneiss

Iron-Stained Quartzite

Recrystallized Meta-Quartzite (primarily SiO2)

Quartz (Smoky/Milky variety with inclusion)

Silicon Dioxide (SiO2)

Quartz Pebble

Silicon Dioxide (SiO2)

Granite

Granite (Felsic Plutonic Rock)

Gneiss

High-grade regional metamorphic rock (Foliated)

Gneiss

Foliated Metamorphic Rock (Gneiss)

Milky Quartz with Epidote or Chlorite inclusions

Silicon Dioxide (SiO2) with inclusions of Epidote {Ca2}{Al2Fe3+}(Si2O7)(SiO4)O(OH)

Quartzite (River Stone)

Quartzite (composed primarily of Silicon Dioxide, SiO2)

Quartz Pebble

Silicon Dioxide (SiO2)

Sandstone (Greywacke/Lithic Sandstone)

Arenite / Lithic Sandstone

Moonstone (Feldspar)

Orthoclase or Oligoclase (KAlSi3O8)

Chrysocolla on Matrix

Hydrated copper phyllosilicate mineral (Cu,Al)2H2Si2O5(OH)4·nH2O

Pink Granite

Phaneritic Plutonic Igneous Rock (composed of K-feldspar, Quartz, and Mica)

Granite

Felsic Plutonic Rock (primarily SiO2, Al2O3, K2O, Na2O)

Granite

Phaneritic plutonic rock (composed mainly of SiO2, Al2O3, K2O, and Na2O)

Pink Granite

Phaneritic Plutonic Rock (Granite with K-Feldspar)

Basalt with Quartz Veins

Basalt (composition: SiO2, MgO, FeO, Al2O3, CaO)

Granite

Granite (Phaneritic igneous rock)

Tourmalinated Quartz

Silicon Dioxide (SiO2) with inclusions of Schorl (NaFe2+3Al6Si6O18(BO3)3(OH)3OH)

Quartz Pebble (with potential iron inclusions)

Silicon Dioxide (SiO2)

Granite

Granite (Phaneritic intrusive igneous rock)

Quartz Pebble

Silicon Dioxide (SiO2)

Granite

Granite (Silicic Plutonic Rock)

Quartz Vein in Host Rock (Pebble)

Quartz (SiO2) with sandstone or siltstone matrix

Native Copper with Cuprite and Quartz

Copper (Cu), Cuprite (Cu2O), Quartz (SiO2)

Howlite

Calcium borosilicate hydroxide (Ca2B5SiO9(OH)5)

Quartz Pebble (with Mica or Iron staining)

Silicon Dioxide (SiO2)

Gneiss (specifically a Granitic Gneiss specimen)

Gneiss (high-grade metamorphic rock primarily composed of Quartz, Feldspar, and Biotite/Amphibole)

Garnet Schist

Almandine Garnet Schist

Quartz pebble (Quartztite fragment)

Silicon Dioxide (SiO2)

River Stone (Granitic Gneiss)

Foliated Granitic Gneiss

Bull Quartz (Milky Quartz)

Silicon Dioxide (SiO2)

Sandstone with Quartz Veining

Clastic sedimentary rock (SiO2 dominated)