Sedimentary Or Igneous Fragment

Mica-rich metamorphic rock, likely biotite schist

Biotite–quartz schist; probable composition of quartz, biotite, feldspar, and minor sulfide or iron-oxide minerals

Mica-rich Schist fragment

Mica Schist

Fossiliferous limestone fragment

Calcitic limestone; mainly calcium carbonate (CaCO₃), possibly with shell or coral debris

Likely rough quartz fragment

Quartz (SiO₂), possibly iron-stained or included quartz

Quartz Geode

Silicon Dioxide (SiO2)

Weathered quartz-rich stone, likely milky quartz

Quartz (SiO₂), possibly a quartz-rich metamorphic or igneous fragment

Quartz fragment

Quartz (silicon dioxide, SiO₂)

Quartz fragment

Quartz (silicon dioxide, SiO₂)

Quartz Pebble

Silicon Dioxide (SiO2)

Chalcedony (Smoky Quartz or Agate nodule fragment)

Silicon Dioxide (SiO2)

Metallic sulfide mineral fragment, likely galena

Galena (lead sulfide, PbS), tentative identification

Conical fossil shell or shell fragment

Likely a gastropod shell fragment; exact taxon indeterminate from the image

Weathered iron-rich rock, possibly basalt or ironstone

Uncertain; likely weathered basalt (plagioclase–pyroxene) or hematite/goethite-bearing ironstone

Quartz

SiO2 (Silicon Dioxide)

Weathered foliated metamorphic rock, likely schist or gneiss

Micaceous schist/gneiss; composition likely quartz, feldspar, mica, and altered mafic minerals

Small rounded pebble, likely quartz-rich sandstone or granitoid fragment

Uncertain; probable quartz/feldspar-bearing lithic pebble

Unopened Geode

Geode (containing various mineralization like Quartz SiO2)

Natural freshwater pearls

Pearl (nacreous calcium carbonate; chiefly aragonite, CaCO₃)

Milky Quartz with Mineral Inclusions

Silicon Dioxide (SiO2)

Druzy Quartz (part of a Geode)

Silicon Dioxide (SiO2)

Quartz Geode

Silicon Dioxide (SiO2)

Weathered schist or gneiss fragment

Quartz–feldspar–mica metamorphic rock; likely mica schist or gneiss

Weathered quartz-bearing metamorphic rock, likely mica schist or gneiss

Quartz–feldspar–mica assemblage; exact mineral identification requires testing

Weathered metamorphic rock, likely schist or gneiss

Quartz–feldspar–mica metamorphic rock; exact identification requires testing

Small pale mineral/rock fragment

Indeterminate; possibly weathered quartz, calcite, or light-colored limestone

Chalcedony (Agate/Quartz)

Silicon Dioxide (SiO2)

Quartz Crystal Fragment

Silicon Dioxide (SiO2)

Weathered quartz-bearing rock, possibly calcite vein fragment

Indeterminate; likely quartz (SiO₂) with carbonate minerals such as calcite (CaCO₃)

Small weathered mineral/rock fragment

Indeterminate; possibly quartz-bearing feldspathic rock or calcite-rich specimen

Quartz

Silicon Dioxide (SiO2)

Quartz

Silicon Dioxide (SiO2)

Gneiss

Metamorphic Gneiss (High-grade regional metamorphism)

Quartz fragment

Quartz (silicon dioxide, SiO₂)

Geode

Quartz / Chalcedony nodule

Quartz-bearing granite or pegmatite fragment

Likely granitic material composed mainly of quartz (SiO₂), feldspar, and possibly biotite or hornblende

Weathered quartz-rich metamorphic rock, likely gneiss or quartzite

Quartz–feldspar–mica metamorphic rock; exact identification is uncertain from the photograph

Quartz Geode

Silicon Dioxide (SiO2)

Likely weathered quartz-rich rock fragment

Uncertain; possibly quartz-bearing granitic or metamorphic material (SiO₂-dominant)

Rounded river pebble, likely quartz-rich sandstone or weathered igneous rock

Indeterminate; possibly quartzite, sandstone, or fine-grained granitic rock

Geode

Quartz / Chalcedony nodule

Quartz Pebble

Silicon Dioxide (SiO2)

Gneiss (with Garnet)

Gneiss (Feldspar-Quartz-Biotite-Garnet Metamorphic Rock)