Sedimentary Or Igneous Fragment

Quartz Crystal Fragment

Quartz (Silicon Dioxide, SiO2)

Quartz

Silicon Dioxide (SiO2)

Quartz (Iron-stained)

Silicon Dioxide (SiO2)

Quartz / Quartz Geode fragment

Silicon Dioxide (SiO2)

Small tumbled quartz-like pebble

Likely quartz (SiO₂), possibly iron-stained chalcedony or feldspar

Yellow chalcedony or quartz fragment

Microcrystalline quartz, SiO₂ (tentative; possibly iron-stained chalcedony)

Small pale mineral fragment

Unidentified; possibly quartz, calcite, or feldspar

Quartz Geode Fragment

Silicon Dioxide (SiO2)

Quartz Geode Fragment

Silicon Dioxide (SiO2)

Likely magnetite-rich rock fragment

Magnetite (Fe₃O₄), possibly in a fine-grained host rock

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

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

Granite or granitic rock fragment

Granitic rock, chiefly quartz, feldspar, and mica

Geode

Quartz / Chalcedony nodule

Weathered brown stone, possibly basalt or iron-rich sedimentary rock

Indeterminate from photograph; likely fine-grained mafic rock (basalt) or ferruginous sandstone

Gneiss (with Garnet)

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

Fluorite with Quartz coating

Calcium Fluoride (CaF2) with Silicon Dioxide (SiO2)

Biotite-rich schist (probable)

Mica schist, likely biotite–quartz–feldspar schist; exact minerals require testing

Mica-rich schist

Mica schist, likely quartz–mica schist (quartz with muscovite and/or biotite)

Garnet in Host Rock

Garnet Group (A3B2(SiO4)3)

Geode

Quartz nodule / Chalcedony-lined cavity

Foliated metamorphic rock (likely mica schist)

Mica schist, typically composed of quartz and mica (muscovite and/or biotite)

Banded quartz-rich metamorphic rock (likely quartzite or quartz-mica schist)

Quartzite/schist composed chiefly of SiO₂ quartz with mica, feldspar, and iron-oxide or copper-colored accessory minerals

Red Jasper

Silicon Dioxide (SiO2) with Iron Oxide inclusions

Mica-rich schist (likely biotite schist)

Mica schist, composed mainly of biotite and/or muscovite with quartz and feldspar

Polished garnet-bearing gneiss

Biotite-quartz-feldspar gneiss with almandine garnet (garnet: Fe₃Al₂(SiO₄)₃)

Quartz (Smoky or Clear variety with inclusions)

Silicon Dioxide (SiO2)

Mica-rich schist (likely quartz-mica schist)

Quartz–mica schist, commonly containing muscovite and/or biotite with quartz and feldspar

Quartz (Milky/Clear Fragment)

Silicon Dioxide (SiO2)

Massive White Quartz

Silicon Dioxide (SiO2)

Quartz Crystal (Geode Fragment)

Silicon Dioxide (SiO2)

Quartz Geode Fragment

Silicon Dioxide (SiO2)

Small rounded pebble, likely quartz-rich river stone

Indeterminate; likely quartz/chert-bearing lithic clast

Weathered sandstone

Quartz-rich sandstone (lithified arenite)

Quartz (Milky/Sugar variety)

Silicon Dioxide (SiO2)

Clear quartz fragment

Quartz (silicon dioxide, SiO₂)

Sand and Gravel (Quartz-rich)

Unconsolidated fluvial/beach sediment (primarily Silica/SiO2)

Crushed Stone Gravel

Crushed Limestone or Granite aggregate

Small translucent mineral fragment, possibly quartz

Quartz (SiO₂), tentative identification

Uncertain blue-white mineral fragment

Possibly calcite or quartz; identification is limited because the specimen is tiny and partly translucent

Quartz vein fragment

Milky quartz (SiO₂), possibly with weathered host rock

Gneiss

Gneiss

Quartz Druzy (on Geode Fragments)

Silicon Dioxide (SiO2)