Mineral In A Matrix (Likely Quartz Or Feldspar)

Quartz Vein in Host Rock (likely Sandstone or Mudstone)

Silicon Dioxide (SiO2) within Sedimentary Matrix

Rhyolite

Rhyolite

Weathered quartz-rich pebble

Milky quartz, chiefly silicon dioxide (SiO₂), possibly with iron-oxide staining and minor feldspar

Sandstone (with vugs or solution cavities)

Arenite (primarily Quartz and Feldspar with CaCO3 or SiO2 cement)

Dalmatian Stone (Dalmatian Jasper)

Peralkaline Aplite (Quartz, Feldspar, and Arfvedsonite composition)

Banded River Pebble (Gneiss or Quartz-Veined Basalt)

Polished River Siltstone or Quartzite Gneiss

River Stone (Sandstone or Siltstone)

Sedimentary Rock (Clastic)

Porphyritic Basalt

Aphanitic-Porphyritic Basalt

Quartz-Veined Sandstone

Quartz-veined Arenite

Orbicular granite (likely larvikite or related granitic rock)

Granite composed mainly of quartz, feldspar, and dark mafic minerals; exact variety is uncertain from the image

Rhyolite Porphyry

Rhyolite (High-silica volcanic rock)

Quartz-rich conglomeratic sandstone

Lithic arkose/conglomerate, dominated by quartz and feldspar grains

Quartz-rich pegmatite with drusy quartz

Quartz (SiO₂) in a granitic pegmatite, likely with feldspar and mica inclusions

Quartz-rich breccia or altered granite fragment

Polymineralic quartz–feldspar rock, likely hydrothermally altered granite/pegmatite

Quartz-rich feldspathic rock, likely rose quartz-bearing granite or pegmatite

Granite/pegmatite composed mainly of quartz (SiO₂) and feldspar, with iron-oxide staining

Quartz with Mica/Host Rock

Silicon Dioxide (SiO2) with Phyllosilicates

Quartz Vein in Matrix

Silicon Dioxide (SiO2) within Rhyolitic or Granitic Matrix

Weathered igneous rock fragment, possibly granite or granitic gneiss

Indeterminate; likely quartz–feldspar–mica aggregate (granite), possibly foliated gneiss

Sandstone (Banded)

Arenite

Porphyritic polymictic breccia (likely volcanic breccia)

Volcanic breccia; probable polymictic andesite–dacite breccia with quartz/feldspar clasts

Quartz-rich pegmatite (likely feldspar–quartz rock)

Granitic pegmatite; chiefly quartz (SiO₂) and feldspar, with minor mica and dark accessory minerals

Quartz with Matrix

Silicon Dioxide (SiO2)

Quartz-bearing granite or granitic gneiss

Granite; primarily quartz (SiO₂), feldspar, and mica, possibly weakly metamorphosed

Ocean Jasper (Orbicular Jasper)

Spherulitic Chalcedony/Rhyolite (SiO2)

Pegmatite with muscovite mica

Granitic pegmatite; quartz (SiO₂), feldspar, and muscovite (KAl₂(AlSi₃O₁₀)(OH)₂), locally biotite/tourmaline

Dalmatian Jasper

Peralkaline Feldspar Rhyolite

Quartz-rich granitic rock, possibly pegmatite

Granite/pegmatitic granite; chiefly quartz (SiO₂), feldspar, and mica

Porphyritic granite (likely weathered granitic rock)

Granite; chiefly quartz, alkali feldspar, plagioclase, and biotite/hornblende

Biotite-bearing granite or granitic gneiss

Quartz–feldspar–biotite aggregate; likely granite, possibly weathered gneiss

Dalmatian Stone (Dalmatian Jasper)

Peralkaline Quartz-Feldspar Porphyry with Arfvedsonite

Quartz (on matrix)

Quartz (Silicon Dioxide, SiO₂)

Quartz Veined Basalt

Mafic Igneous Rock with Quartz (SiO2) intrusion

Quartz-rich pegmatite (likely granite/pegmatite boulder)

Coarse-grained felsic igneous rock, chiefly quartz (SiO₂), feldspar, and minor mica; exact identification requires testing

Conglomerate (or Breccia / Porphyry)

Clastic Sedimentary Rock (Conglomerate / Sandstone)

Quartz-rich feldspathic rock, likely granite or granitic gneiss

Granite/granitic gneiss; chiefly quartz (SiO₂), feldspar, and minor mica

Granite

Granite (a common term for a felsic intrusive igneous rock)

Garnet in Matrix (likely Almandine in Quartz/Mica Schist)

Almandine Garnet (Fe3Al2(SiO4)3) in Quartz-Feldspar host rock

Porphyritic Basalt (with Lath-like Phenocrysts)

Porphyritic Basalt

Biotite-bearing granite or granitic pegmatite fragment

Granite/pegmatite; quartz (SiO₂), feldspar, and biotite mica

Quartz–feldspar pegmatite with garnet

Granitic pegmatite; chiefly quartz (SiO₂), feldspar, mica, and reddish-brown almandine garnet

Granite

Phaneritic Plutonic Felsic Rock (Quartz/Feldspar/Mica)

Garnetiferous Pegmatite

Pegmatite with Almandine Garnet and Muscovite