Sedimentary Or Igneous Fragment

Granite fragment

Granite, a coarse-grained felsic intrusive igneous rock composed mainly of quartz, feldspar, and mica

Granite fragment

Granite, chiefly quartz, feldspar, and mica

Granite fragment

Granite, chiefly quartz (SiO₂), feldspar, and mica

Granite fragment

Granite, chiefly quartz, alkali feldspar, plagioclase, and mica

Granite fragment

Felsic intrusive igneous rock; mainly quartz, alkali feldspar, plagioclase, and minor biotite/hornblende

Quartz-rich rock fragment (tentative)

Quartz, silicon dioxide (SiO₂), possibly in a weathered host rock

Worn quartz-rich pebble

Likely microcrystalline quartz (SiO₂), possibly a weathered chert or milky quartz fragment

Mica-rich granite or pegmatite fragment

Feldspar–quartz rock with dark mica, likely biotite; exact identification is uncertain from the photo

River Pebble

Polished lithic fragment

Pebble / Gravel Fragment

Clastic Rock Fragment

River Pebble

Siliceous rock fragment

Breccia

Clastic Breccia

Small rough quartz crystal or quartz fragment

Quartz (silicon dioxide, SiO₂)

Milky quartz with iron staining

Quartz, SiO₂

Milky quartz

Quartz (SiO₂)

Volcanic tuff and basalt outcrop

Welded volcanic tuff, with probable basaltic lava/scoria

Weathered shale or mudstone fragment

Fine-grained clastic sedimentary rock, likely shale or mudstone; exact identification is uncertain from the photo

Weathered breccia or conglomeratic sandstone

Clastic sedimentary rock, likely carbonate-cemented breccia/conglomerate

Fossilized Shell Fragment

Invertebrate marine fossil, likely calcium carbonate replacement

Quartz Geode

Silicon Dioxide (SiO2) within a sedimentary or igneous host

Mixed collection of natural stones

Several unidentified lithologies, likely including basalt, granite, quartzite, sandstone, and weathered metamorphic rocks

Likely petrified wood

Silicified wood; fossilized plant tissue, commonly replaced by quartz (SiO₂)

Basalt Fragment

Basalt (Aphanitic Mafic Igneous Rock)

Granite fragment

Phaneritic Igneous Rock (Granitic composition)

Quartz-bearing metamorphic rock, likely garnet-mica schist

Quartz–mica schist with probable garnet and iron-oxide minerals

Weathered sedimentary rock, likely fine-grained sandstone or siltstone

Quartz-rich sandstone/siltstone; exact identification requires close examination

Weathered granite or granitic rock

Granite; chiefly quartz, feldspar, and mica, with possible iron-oxide staining

Weathered quartz-rich rock, possibly granite or quartzite

Likely quartz–feldspar aggregate; precise identification requires testing

Weathered feldspar-rich granite fragment

Granite, primarily quartz (SiO₂), feldspar, and mica

Weathered granite or granitic pegmatite fragment

Granite; chiefly quartz (SiO₂), feldspar, and minor biotite/hornblende

Likely clear quartz fragment

Quartz (silicon dioxide, SiO₂)

Unidentified rough rock fragment

Indeterminate; the image does not show enough detail for a reliable mineral or rock identification

Small dark rock fragment (not identifiable from the image)

Undetermined; no diagnostic mineral features are visible

Yellow quartz pebble

Quartz, SiO₂ (likely iron-stained milky quartz)

White quartz pebble

Quartz (SiO₂), likely milky quartz

Small reddish-brown mineral fragment, likely quartz-bearing rock

Indeterminate; possibly iron-stained quartz or feldspar-rich stone

Likely weathered quartz-rich pebble

Uncertain; possibly granite or quartz-bearing volcanic rock

Uncertain green-brown mineral fragment

Possibly epidote, chlorite, or altered amphibole; exact identification requires testing

Tumbled pink feldspar pebble

Potassium feldspar, commonly microcline or orthoclase (KAlSi₃O₈)

Quartz-rich metallic-looking pebble

Likely quartz or quartzite; exact identification is uncertain from the blurred image

Gold-bearing dark rock, possibly magnetite with iron-oxide staining

Likely magnetite (Fe₃O₄) with limonite/goethite; metallic patches may be gold or weathered sulfide, unconfirmed

Iron-stained quartz-rich cobble, possibly weathered granite or quartz vein rock

Quartz–feldspar aggregate with iron-oxide staining; exact classification is uncertain from the photograph