Metamorphic, Likely Sedimentary With Quartz Veins

Quartz (Small Fragment)

Silicon Dioxide (SiO2)

Milky Quartz

Silicon Dioxide (SiO2)

Iron-stained quartz-rich rock, possibly gold-bearing quartz

Quartz (SiO₂) with iron-oxide staining; possible limonite/goethite matrix

Quartz Vein in Pelite (Metamorphic Rock)

Hydrothermal Quartz Veining in Metasedimentary Rock (SiO2)

Milky Quartz Pebble with Iron staining

Silicon Dioxide (SiO2)

Tumbled green aventurine (likely)

Quartz, SiO₂, containing green fuchsite mica or other inclusions

Mixed Mineral Collection (with Quartz, Beryl, and host rock)

Silicon Dioxide (Quartz), Be3Al2Si6O18 (Beryl), and associated Schist/Pegmatite

Milky quartz vein fragment

Quartz (silicon dioxide, SiO₂), massive/microcrystalline variety

Likely quartz-bearing mineral aggregate

Quartz (SiO₂), possibly mixed with mica or feldspar

Iron-stained quartz vein fragment

Quartz (SiO₂), likely with limonite/goethite iron oxides and minor sulfides

Milky Quartz

Silicon Dioxide (SiO2)

White quartz pebble

Quartz (silicon dioxide, SiO₂)

Banded gneiss pebble

Gneiss, commonly quartz–feldspar–mica gneiss

Milky Quartz

Silicon Dioxide (SiO2)

Quartz (milky quartz), possibly calcite

Quartz: SiO₂; visual identification is uncertain because the specimen is wet and lacks diagnostic crystal faces

Quartz-Veined Slate or Greenstone

Metamorphic rock with quartz vein (SiO2)

Likely weathered metamorphic rock (quartzite or schist)

Quartz-rich foliated metamorphic rock; exact identification requires testing

Epidote in Matrix (likely Amphibolite or Gneiss)

Epidote (Ca2(Al2,Fe)(SiO4)(Si2O7)O(OH)) in Metamorphic Matrix

Yellow Chalcedony (Agate/Chert)

Cryptocrystalline Quartz (SiO2)

Small pale mineral fragment

Unidentified; possibly quartz, calcite, or feldspar

Quartz Vein in Matrix (Breccia / Host Rock with Quartz)

Silicon Dioxide (SiO2) in Host Rock Matrix

Tumbled epidote-bearing rock (likely epidote–quartz–feldspar aggregate)

Epidote-rich metamorphic rock; minerals likely epidote (Ca₂(Al,Fe)₃Si₃O₁₂(OH), quartz, feldspar, and dark amphibole/biotite)

Mixed river stones and gravel

Polymictic alluvial clasts; individual pieces may include quartzite, granite, basalt, sandstone, limestone, and slate

Tumbled milky quartz

Quartz (silicon dioxide, SiO₂)

Milky quartz (likely quartz-rich rock)

Quartz, silicon dioxide (SiO₂)

Banded metamorphic rock, likely gneiss

Biotite–quartz–feldspar gneiss, possibly amphibolite-bearing

Mixed collection of common river stones

Varied lithologies, visibly including quartz-rich rock, dark mafic rock, sandstone, and purple quartz-bearing material

Dark gray metamorphic rock, likely hornfels or fine-grained amphibolite

Hornfels/amphibolite; commonly quartz, feldspar, amphibole, biotite, and minor sulfides

Tumbled blue stone, likely blue aventurine or dyed quartz

Quartz (SiO₂), possibly with fuchsite inclusions; exact identification requires testing

Weathered quartz-rich pebble (probable quartzite or quartz vein fragment)

Quartzite, predominantly silicon dioxide (SiO₂); exact identification is uncertain from the photograph

Mixed rock and mineral collection

Multiple specimens; visible pieces may include quartz, calcite, agate/chalcedony, jasper, and dyed or coated materials

Chert (potentially Jasper or Agatized Chert)

Microcrystalline Quartz (SiO2)

Amethyst and Calcite collection

Silicon Dioxide (SiO2) and Calcium Carbonate (CaCO3)

Milky Quartz

SiO2 (Silicon Dioxide)

Quartz (Rose Quartz or Jasper variety)

Silicon Dioxide (SiO2)

Quartz Crystal

Silicon Dioxide (SiO2)

Quartzite

Quartzite (SiO2)

Gneiss (with Quartz-Feldspar vein)

Gneiss (high-grade metamorphic rock) containing Quartz (SiO2) and Feldspar (KAlSi3O8 – NaAlSi3O8 – CaAl2Si2O8)

Quartz (likely Jasper or Chert variety)

Quartz (SiO₂)

Quartz

Silicon Dioxide (SiO2)

Weathered fine-grained stone, likely sandstone or quartzite

Quartz-rich sandstone (possibly weakly metamorphosed quartzite); predominantly SiO₂

Quartz (Vein Quartz)

Silicon Dioxide (SiO2)