Igneous And Metamorphic Derivative (Weathered)

Milky Quartz with inclusions

Silicon Dioxide (SiO2)

Tumbled pale-yellow quartz (likely citrine or iron-stained quartz)

Quartz, silicon dioxide (SiO₂); yellow color likely from iron-related impurities

Quartz pebble with a conchoidal chip

Silicon dioxide (SiO2)

Quartz Pebble

Silicon Dioxide (SiO2) Pebble

Quartz (Grain)

Silicon Dioxide (SiO2)

Tumbled milky quartz pebble

Quartz (silicon dioxide, SiO₂), likely milky quartz

Tumbled quartz-rich stone, possibly milky quartz or calcite

Quartz (SiO₂) or calcite (CaCO₃); exact identification requires testing

Quartz Pebble

Silicon Dioxide (SiO2)

Milky Quartz Pebble

Quartz (Silicon Dioxide - SiO2)

Quartz Pebble

Silicon Dioxide (SiO2)

Native Gold (in Jewelry)

Gold (Au)

Likely weathered mica-rich rock fragment

Probable schist, composed mainly of quartz, feldspar, and mica

Quartz Vein in Host Rock

Silicon Dioxide (SiO2) within Metasedimentary or Igneous Matrix

Quartz (Vein Quartz)

Silicon Dioxide (SiO2)

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

Banded gneiss (possibly migmatitic gneiss)

Quartz–feldspar–mica gneiss; composition commonly includes quartz, feldspar, biotite/hornblende, and accessory dark minerals

Granite or Quartzite fragment

Granite / Quartzite

Quartz

Silicon Dioxide (SiO2)

Magnetite (potentially as a Lodestone or within Ironstone)

Magnetite (Fe3O4)

Rounded gray river pebble, likely basalt or andesite

Fine-grained mafic to intermediate volcanic rock; exact identification requires testing

Labradorite-bearing gneiss or schist

Feldspathic gneiss/schist containing iridescent labradorite (plagioclase feldspar, NaAlSi₃O₈–CaAl₂Si₂O₈)

Quartz Pebble

Silicon Dioxide (SiO2)

Mica-rich schist (likely biotite schist)

Biotite–quartz–feldspar schist; composition varies

Biotite Mica

Biotite (K(Mg,Fe)3(AlSi3O10)(F,OH)2)

Gold Ore in Matrix

Native Gold (Au) in Quartz/Limonite host rock

Quartz

Silicon Dioxide (SiO2)

Likely basalt (possibly weathered volcanic rock)

Basalt; predominantly plagioclase feldspar and pyroxene, with possible olivine and iron oxides

Weathered granitoid (likely granite or granitic gneiss)

Granite; chiefly quartz, feldspar, and mica (exact identification uncertain from the photo)

Weathered quartz-rich cobble, likely milky quartz

Quartz (SiO₂), possibly ferruginous milky quartz

Bornite (Peacock Ore)

Bornite (Cu5FeS4)

Likely polished/tumbled dark mineral or glassy rock fragment

Indeterminate from image; possibly hornblende, schorl tourmaline, or obsidian

Biotite (Black Mica)

K(Mg,Fe)3AlSi3O10(OH,F)2

Milky quartz vein rock

Quartz (SiO₂), likely in a quartz-rich host rock with minor iron-stained minerals

Milky quartz pebble

Quartz (silicon dioxide, SiO₂)

Milky quartz pebble

Quartz (silicon dioxide, SiO₂)

Weathered quartz-rich cobble, possibly granitic gneiss

Probable quartz–feldspar–mica aggregate; exact lithology uncertain from image

Quartz-rich rock, possibly milky quartz or quartzite

Quartz (silicon dioxide, SiO₂); if granular and foliated, likely quartzite

Moonstone with Black Tourmaline

Feldspar (KAlSi3O8) with inclusions of Schorl (NaFe3Al6(BO3)3Si6O18(OH)4)

Milky quartz

Quartz, silicon dioxide (SiO₂)

Quartz Pebble

Silicon Dioxide (SiO2)

Banded gneiss (likely weathered paragneiss)

Gneiss; quartz–feldspar–mica ± amphibole assemblage

Quartz (Clear/Crystalline)

Silicon Dioxide (SiO2)