Mineral, Possibly Rock Fragment Containing A Mineral

Kimberlite

Ultramafic igneous rock

Dark rock/mineral fragment

Undetermined; possibly magnetite-rich basalt or iron sulfide

Likely quartz-rich rock fragment

Quartz (SiO₂), possibly iron-stained or mixed with feldspar

Quartz-rich feldspathic rock, possibly granite or pegmatite fragment

Granite/pegmatite; chiefly quartz (SiO₂), feldspar, and minor dark mica or amphibole

Quartz Pebble (Geode Fragment / Druzy Cavity)

Silicon Dioxide (SiO2)

Small pale rock fragment

Indeterminate; possibly quartz, calcite, or a weathered feldspar-rich fragment

Unidentified metallic mineral fragment

Indeterminate; possibly galena, hematite, or a metallic meteorite fragment

Porous fossiliferous limestone

Calcitic limestone, predominantly calcium carbonate (CaCO₃), possibly bioclastic or weathered reef limestone

Quartz-rich rock, possibly milky quartz or quartzite

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

Likely weathered gray stone, possibly basalt

Basalt (tentative; aphanitic mafic volcanic rock)

Tumbled brecciated jasper

Silica-rich microcrystalline quartz/chalcedony (SiO₂), with iron-oxide and other mineral inclusions

Likely raw quartz-bearing stone, possibly greenish quartz or calcite

Uncertain from photograph; possible quartz (SiO₂) or calcite (CaCO₃)

Small pale-green stone, possibly serpentine or quartz

Undetermined from the image; no diagnostic features confirm a specific mineral

Weathered limestone or concrete-like calcareous rock

Limestone; predominantly calcite (CaCO₃), possibly containing dolomite and silicate impurities

Greenish rough stone, possibly serpentine or soapstone

Indeterminate from the image; possible serpentinite (serpentine-group minerals) or talc-rich soapstone

Fossilized tooth fragment, possibly a mammalian tooth

Indeterminate fossil tooth; enamel and dentine, taxon not identifiable from this fragment

Possible weathered iron-rich rock or slag fragment

Indeterminate; likely limonite/goethite-bearing material, possibly iron slag

Sedimentary Rock Fragments

Clastic Sedimentary Rock

Small white mineral fragment

Likely quartz (SiO₂), possibly calcite (CaCO₃)

Quartz-rich mineral fragment

Quartz (silicon dioxide, SiO₂), possibly milky quartz

Uncertain small stone; possibly weathered quartz-bearing rock

Indeterminate from image; candidate materials include quartz-rich pebble or altered silicate rock

Quartz-rich vein fragment, possibly quartz with mica or calcite

Quartz (SiO₂), with probable muscovite/biotite mica and minor feldspar or calcite

Quartz geode fragment

Microcrystalline quartz (SiO₂), possibly with iron-oxide staining or an unidentified dark mineral inclusion

Small rounded limestone pebble

Limestone, predominantly calcite (CaCO₃), possibly fossiliferous or oolitic

Polished blue-gray mineral specimen, likely galena-bearing ore

Galena (PbS), possibly mixed with quartz/calcite and secondary copper minerals

Small brown mineral fragment, possibly quartz/chert

Uncertain; likely microcrystalline quartz (SiO₂) or a weathered silicate rock

Unidentified pale stone or mineral specimen

Indeterminate; possibly massive quartz, calcite, or a light-colored feldspathic rock

Metallic sulfide-bearing rock, possibly galena-bearing ore

Probable galena (PbS) with pyrite and quartz/matrix; exact identification requires testing

Pegmatitic granite fragment

Granitic pegmatite, chiefly quartz, feldspar, and mica

Fossiliferous limestone pebble

Bioclastic limestone, chiefly calcite (CaCO₃), possibly containing small fossil fragments

Unidentified dark, flat specimen

Indeterminate; image resolution is insufficient for mineral identification

Granite fragment

Granite

Serpentine-rich greenstone (probable serpentine/soapstone fragment)

Serpentine-group minerals, chiefly antigorite/lizardite; possibly minor talc, chlorite, and carbonate

Small dark mineral or rock fragment

Indeterminate; possibly mica-rich schist, biotite, or a dark sulfide mineral

Reddish weathered rock, possibly jasper or iron-rich chert

Microcrystalline quartz (SiO₂), if jasper/chert; abundant iron oxides such as hematite/goethite

Small quartz-rich mineral fragment

Quartz (SiO₂), possibly milky or chalcedonic quartz

Iron-stained quartz-rich rock (possibly ironstone)

Quartz (SiO₂) with iron-oxide/hydroxide staining, likely limonite/goethite

Polymictic conglomerate or breccia (possibly concrete-like aggregate)

Lithified polymictic gravel; clasts may include basalt, granite, quartzite, and other silicates

Quartz-rich feldspathic rock, possibly granite or pegmatite

Granite/pegmatite; primarily quartz (SiO₂) and feldspar, with possible mica

Tourmaline-rich schist (likely black tourmaline)

Schist containing schorl, Fe-rich NaFe3Al6(BO3)3Si6O18(OH)4

Weathered sandstone or volcanic rock fragment

Indeterminate; likely quartz–feldspar-rich sandstone, possibly altered volcanic rock

Unidentified gray rock fragment

Indeterminate from image; possibly quartz- or feldspar-rich silicate material