Sedimentary Or Igneous Fragment

Fossiliferous limestone, likely coral or shell-rich fragment

Calcite (CaCO₃), commonly bioclastic limestone containing fossilized marine organisms

Likely garnet-bearing schist or gneiss

Mica schist/gneiss containing quartz, feldspar, mica, and probable almandine garnet

Small pale mineral fragment

Indeterminate; possibly quartz or calcite

Quartz (or Chalcedony) Specimen

Silicon Dioxide (SiO2)

Yellow quartz fragment (likely citrine or iron-stained quartz)

Quartz, silicon dioxide (SiO₂), trigonal crystal system

Gravel / Crushed Stone

Aggregate (mixed mineral rock fragments)

Small quartz fragment (tentative)

Quartz, silicon dioxide (SiO₂)

Small quartz-rich pebble or rock fragment

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

Weathered sandstone fragment

Clastic sandstone, likely quartz-rich (quartz arenite or arkose)

Biotite mica schist (probable)

Schist dominated by biotite mica; commonly quartz–feldspar–biotite

Unidentified Rock Fragment

Unknown

Green Aventurine

Silicon Dioxide (Quartz with Fuchsite inclusions), SiO2

Quartz Grain / Sandstone Fragment

Silicon Dioxide (SiO2)

Milky quartz fragment

Quartz (silicon dioxide, SiO₂)

Quartz (Small Fragment)

Silicon Dioxide (SiO2)

Quartz chunk

Silicon dioxide (SiO2)

Unknown dark mineral/rock fragment

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

Unidentified polished stone fragments

Indeterminate; likely mixed lapidary specimens, possibly jasper, agate, or quartz-bearing rock

Biotite-rich schist (mica schist)

Mica schist, chiefly biotite (K(Mg,Fe)₃AlSi₃O₁₀(OH,F)₂), with possible quartz and feldspar

Weathered schist or gneiss

Quartz–feldspar–mica metamorphic rock

Gneiss

Gneissic Metamorphic Rock

Milky quartz fragment

Quartz (silicon dioxide, SiO₂)

Weathered schist or gneiss cobble

Foliated silicate rock, likely mica schist or biotite gneiss

Arkosic Sandstone (or Conglomeritic Sandstone fragment)

Arkose (rich in feldspar)

Clear quartz fragment

Quartz, silicon dioxide (SiO₂)

Quartz (Grain/Fragment)

Silicon Dioxide (SiO2)

Geode with Quartz Crystals

SiO2 (Silicon Dioxide) in a geode formation

Dark gray rock fragment, likely basalt

Basalt; chiefly plagioclase feldspar and pyroxene, commonly with minor olivine and magnetite

Quartz (Milky/Snow)

Silicon Dioxide (SiO2)

Likely quartz-rich gravel fragment (uncertain identification)

Quartz, silicon dioxide (SiO₂), possibly mixed with feldspar or other light-colored minerals

Weathered quartz-rich pebble (tentative)

Likely quartz/chalcedony, SiO₂, possibly iron-stained

Iron-stained quartz-bearing rock, possibly weathered granite or gneiss

Quartz–feldspar rock with iron-oxide staining; exact identification requires testing

Red Garnet (likely Almandine or Pyrope)

Garnet group: X3Y2(SiO4)3 (e.g., Almandine: Fe3Al2Si3O12)

Small gray translucent stone, possibly quartz or glassy mineral

Uncertain; likely microcrystalline quartz (SiO₂), but the image is insufficient for definitive identification

Clear Quartz

Silicon Dioxide (SiO2)

Quartz

Silicon Dioxide (SiO2)

Unidentified small rock fragment

Likely quartz-rich material; exact identification is indeterminate from the image

Red Jasper

Silicon Dioxide (SiO2) with iron oxide inclusions

Weathered quartz-mica schist

Quartz–muscovite/biotite schist, locally iron-oxide stained

Unidentified small mineral fragments

Likely quartz- or feldspar-rich material; species cannot be determined reliably from the image

Milky Quartz with Iron Staining

Quartz (Silicon Dioxide, SiO2)

Quartz–mica schist or mica-rich quartzite

Quartz with muscovite/biotite mica; likely a quartz-mica schist, possibly pegmatitic