Mineral In A Matrix (Likely Quartz Or Feldspar)

Peach Moonstone (Orange/Peach Feldspar)

Potassium aluminum silicate (KAlSi3O8)

Yellow Quartz Pebble (Citrine or Iron-Stained Quartz)

Silicon Dioxide (SiO2)

Granite (Pink/Red)

Phaneritic Plutonic Felsic Rock (major minerals: Quartz, Orthoclase Feldspar, Plagioclase Feldspar)

Basalt with Quartz/Calcite matrix

Basalt (SiO2 with Ca/Mg/Fe silicates) on a Mineral Matrix

Milky Quartz with Mineral Inclusions

Quartz (Silicon Dioxide - SiO2)

Clear Quartz

Quartz (Silicon Dioxide, SiO2)

Jasper with Quartz Druzy

Silicon Dioxide (SiO2)

Granodiorite

Granodiorite (Quartz + Plagioclase + Alkali Feldspar + Biotite/Hornblende)

Pyrite and Fluorite on Quartz (Matrix Specimen)

Iron Disulfide (FeS2) and Calcium Fluoride (CaF2) with Silicon Dioxide (SiO2)

Quartz Geode in Chert/Limestone Matrix

Silicon Dioxide (SiO2) within Sedimentary Host Rock

Granite

Phaneritic Plutonic Igneous Rock (composed of quartz, alkali feldspar, and plagioclase)

Milky Quartz with inclusions

Silicon Dioxide (SiO2)

Quartz (likely milky/rose quartz variety)

Quartz (SiO2 - Silicon Dioxide)

Sandstone (Quartzite Pebble)

Arenite / Metamorphosed Sandstone (SiO2)

Quartz Druze on Matrix (Geode Fragment)

Quartz (Silicon Dioxide, SiO2)

Druzy Quartz on Chert/Siltstone

Silicon Dioxide (SiO2) on Microcrystalline Silica/Siltstone matrix

Quartz (Clear Quartz/Rock Crystal)

Silicon Dioxide (SiO2)

Puddingstone

Conglomerate (typically quartz-rich or jasper-rich)

Banded Gneiss

Gneiss (High-grade Metamorphic Rock)

River Pebble (Likely Chert or Fine-Grained Sandstone/Quartzite)

Siliciclastic clast (likely Chert or Quartzarenite/Quartzite pebble)

Sandstone

Arenite (SiO2, often with CaCO3 or Fe2O3 cement)

Granite Cobble

Granite (Phaneritic Igneous Rock)

Granite

Granite (phaneritic intrusive igneous rock consisting of quartz, feldspar, and mica)

Quartz Pebble

Quartz (Silicon Dioxide, SiO2)

Granite

Phaneritic plutonic rock (primarily Quartz, Alkali Feldspar, and Plagioclase)

Smoky Quartz

SiO2 (Silicon Dioxide)

Breciated Chert

Brecciated Chert (Microcrystalline Quartz, SiO2)

Granite

Phaneritic plutonic rock (Quartz, Alkali Feldspar, and Plagioclase)

Alexandrite in Matrix

Chrysoberyl (BeAl2O4 with Chromium)

Quartz (Milky/Common)

Silicon Dioxide (SiO2)

Granite

Granitic intrusive igneous rock

Yellow Quartz (Citrine-colored Quartz Pebble)

Silicon Dioxide (SiO2)

Gneiss

Gneiss

Banded Gneiss with Quartz Vein

Foliated Metamorphic Rock (Gneiss)

Quartz (River Pebble)

Silicon Dioxide (SiO2)

Quartz Druze (on Matrix)

Silicon Dioxide (SiO2)

Sandstone

Arenite

Quartz pebble with surface markings

Silicon Dioxide (SiO2)

Sandstone

Arenite (primarily SiO2)

Sandstone

Clastic sedimentary rock (primarily SiO2)

Fossiliferous Chert (Gryphaea Fossil)

Silicon Dioxide (SiO2) with Calcitic Mollusk Remnants

Sandstone (likely Quartzose type)

Clastic sedimentary rock (primarily SiO2)