Mineral, Possibly Rock Fragment Containing A Mineral

Uncertain pale green-gray mineral/rock fragment

Possibly serpentine-bearing rock or greenstone; exact identification requires testing

Fossilized bone fragment

Petrified bone, mineral-replaced vertebrate bone; exact taxon indeterminate

Unidentified small rock or mineral fragment

Indeterminate from the blurred image; possibly quartz-rich stone, feldspar, or weathered concrete-like geological material

Fossiliferous limestone pebble

Bioclastic limestone, commonly calcitic (CaCO₃)

Weathered iron-rich rock, possibly ironstone or altered basalt

Indeterminate; likely ferruginous basalt/ironstone containing hematite-goethite and silicate minerals

Banded Greywacke

Greywacke (Lithic wacke)

White quartz fragment (probable)

Quartz, silicon dioxide (SiO₂)

Weathered conglomerate

Polymictic clast-supported conglomerate, with a sandy or finer-grained matrix

Iron-stained quartz-bearing rock

Quartz (SiO₂), likely with limonite/goethite iron oxides and possibly feldspar

Pale blue-green altered volcanic rock, likely basalt

Altered basalt (fine-grained plagioclase–pyroxene rock with secondary zeolite/chlorite minerals)

Limestone with Fossil Imprints

Biogenic Limestone (Calcium Carbonate, CaCO3)

Unknown brown-and-gold rock fragment

Undetermined; possibly iron-stained quartz, mica schist, or sulfide-bearing ore

Small rough mineral specimen, likely quartz-bearing stone

Indeterminate from image; possibly quartz (SiO₂) with iron-oxide staining

Unknown dark mineral/rock fragment

Indeterminate; possibly a dark sulfide mineral or slag-like geological fragment

Sandstone

Arenite (SiO2 based)

Polished brown mineral or rock fragment

Indeterminate from image; possibly iron-stained quartz, jasper, or a polished sulfide-bearing specimen

Weathered quartz-rich rock, possibly milky quartz or quartzite

Quartz (SiO₂), likely with iron-oxide staining and minor host minerals

Likely weathered quartz-rich pebble

Uncertain; possibly granite or quartz-bearing volcanic rock

Likely weathered metallic mineral or slag fragment

Indeterminate; possibly iron-rich sulfide/oxide material or industrial slag

Granite

Intrusive Igneous Rock

Weathered iron-rich rock, possibly limonite/goethite-bearing breccia

Hydrated iron oxides/hydroxides, mainly limonite (mixture) and goethite, FeO(OH)·nH₂O

Weathered brown rock fragment

Indeterminate; possibly iron-stained sandstone, mudstone, or weathered limestone

Small weathered quartz-rich pebble

Likely quartz (SiO₂), possibly quartzite or feldspar-bearing rock

Red Sandstone with Reduction Spot

Quartzose Sandstone with a Leach/Reduction Spot

Weathered light-colored rock, possibly quartz-rich granite or quartzite

Indeterminate; likely quartz–feldspar rock (granite) or quartzite

Likely galena-bearing rock

Galena (PbS), possibly in a dark host rock

Unidentified weathered rock fragment

Likely granitic or feldspathic rock; exact identification requires clearer imaging and testing

Gravel / Limestone Fragment

Calcium Carbonate (CaCO3) / Fine-grained Sedimentary Rock

Greenish quartz-bearing rock, possibly serpentine or aventurine

Tentatively quartz (SiO₂) with green inclusions; exact identification requires testing

Small quartz-rich pebble or rock fragment

Quartz (silicon dioxide, SiO₂), possibly with iron-oxide staining or host-rock inclusions

Likely gray granite or gneiss fragment

Granite: quartz, feldspar, and mica; possibly banded gneiss if foliation is present

Milky quartz

Quartz (SiO₂), likely massive or drusy quartz

Granite

Intrusive Igneous Rock

Granite (likely)

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

Rounded gray pebble, likely fine-grained metamorphic rock

Possibly quartz-rich gneiss or granofels; exact identification requires closer examination

Quartz-rich breccia or altered granite fragment

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

Small pale mineral fragment

Unidentified; possibly quartz, calcite, or feldspar

Quartz-rich rock fragment, possibly chalcedony or weathered quartz

Silicon dioxide (SiO₂), likely quartz/chalcedony

Asphalt aggregate

Human-made bituminous asphalt containing crushed silicate rock aggregate

Green serpentine or nephrite-like stone

Serpentinite, chiefly serpentine-group minerals; exact identification would require testing

Likely garnet-bearing mica schist

Mica schist, possibly containing garnet (garnet–mica schist)

Sandstone

Arenite (SiO2 primarily)