Sedimentary Or Igneous Fragment

Quartz (Clear / Rock Crystal)

Silicon Dioxide (SiO2)

Orthoclase Feldspar

Potassium aluminum silicate (KAlSi3O8)

Quartz (Milky or Clear Quartz fragment)

Silicon Dioxide (SiO2)

Jasper

Jasper (Silicon Dioxide, SiO2 plus iron oxide impurities)

Fossiliferous Limestone

Calcium carbonate with biological impressions (CaCO3)

Quartz crystal fragment

Quartz (SiO₂), likely a small clear-to-gray crystal fragment

Red shale (likely mudstone)

Iron-oxide-stained clay-rich shale; composition typically clay minerals and fine quartz, with hematite providing the red color

Chert (Flint Flake)

Microcrystalline Quartz (SiO2)

Black Beauty Meteorite

NWA 7034 (Northwest Africa 7034)

Dark rock fragment, possibly basalt

Undetermined; possibly basalt (fine-grained mafic volcanic rock)

Weathered rock fragment (exact type uncertain)

Unidentified fine-grained rock; image does not support a reliable species-level identification

Small quartz-rich rock fragment

Unidentified quartz-bearing rock; the image is insufficient for a precise identification

Granite (small weathered fragment)

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

Unidentified small rock fragment

Undetermined; the photo does not show enough detail for reliable mineral identification.

Small granite fragment

Granite, chiefly quartz, feldspar, and mica

Dark, weathered rock fragment (likely basalt or andesite)

Cannot be reliably identified from the photograph; possibly basaltic to andesitic volcanic rock

Weathered granite fragment

Granite, chiefly quartz, feldspar, and mica

Quartz-rich rock fragment

Likely quartz vein material, predominantly quartz (SiO₂); identification is tentative from the image

Likely basalt or another dark, fine-grained volcanic rock

Basalt (tentative; composition cannot be confirmed from the image)

Granite fragment

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

Dark gray, fine-grained rock fragment (possibly basalt)

Basalt (tentative identification; image alone cannot confirm)

Unidentified rough rock fragment

Indeterminate; no diagnostic mineral or texture can be confirmed from the image

Dark rock fragment, possibly basalt

Unidentified mafic volcanic rock; basalt is a tentative visual identification

Weathered quartz-rich rock fragment

Likely quartz–feldspar-rich granitoid, possibly granite or granitic gneiss; exact identification is uncertain from the image

Gray stone fragment

Unidentified fine-grained gray rock; exact identification is not possible from the image

Weathered quartz- or feldspar-rich rock fragment

Indeterminate light-colored silicate rock; possibly quartz or feldspar in a granitic fragment

Dark gray-blue stone fragment

Unidentified fine-grained rock; the image is insufficient for a reliable species-level identification

Small gray rock fragment

Unidentified rock; the image lacks enough detail for reliable mineral identification

Granite fragment

Granite

Red Jasper

Silicon Dioxide (SiO2) with Hematite inclusions

Fossilized tooth or bone fragment

Indeterminate fossil; possibly a small fossil tooth or mineralized bone, exact identification requires microscopy

Small brown rock fragment, possibly iron-stained quartz or chert

Unidentifiable from the photograph; potentially quartz (SiO₂) or microcrystalline silica (chalcedony/chert)

Small weathered stone, possibly quartz-rich granite or feldspar

Indeterminate granitoid fragment; likely quartz (SiO₂) and feldspar, with minor mica or iron oxides

Pyrite

Iron Sulfide (FeS2)

Likely weathered granite or granitic pegmatite

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

Quartz on Matrix

Silicon Dioxide (SiO2)

Fossiliferous Limestone

Biogenic Limestone

Small brown quartz-rich pebble, possibly chert or jasper

Microcrystalline quartz (SiO₂), tentative

Rounded brown river pebble

Indeterminate lithic fragment; likely weathered sandstone, mudstone, or fine-grained volcanic rock

Quartz-bearing rock, possibly pegmatite

Likely quartz and feldspar with dark mica or other accessory minerals; exact rock type is uncertain from the image

Possible fossil-bearing pebble

Unidentified fine-grained sedimentary rock; the small orange feature may be a fossil or mineral inclusion

Pumiceous volcanic rock (likely rhyolitic pumice/tuff)

Felsic volcanic glass and ash; commonly quartz–alkali feldspar–plagioclase composition