Mineral And Sedimentary

Clear quartz crystal point

Quartz (silicon dioxide, SiO₂)

Pyrite (iron pyrite), possibly in a sulfide-bearing rock

Pyrite, FeS₂

Pyrite

Iron Disulfide (FeS2)

Tumbled quartz (rock crystal)

Quartz, silicon dioxide (SiO₂)

Quartz fragment

Quartz (silicon dioxide, SiO₂)

Likely pyrite-bearing rock fragment

Pyrite (FeS₂), possibly in a weathered host rock; identification is uncertain from the image

Mixed rock and mineral collection

Multiple specimens; visible pieces may include quartz, calcite, agate/chalcedony, jasper, and dyed or coated materials

Blue calcite (probable)

Calcite, calcium carbonate (CaCO₃)

Raw quartz crystal

Quartz (silicon dioxide, SiO₂), likely milky or iron-stained quartz

Mixed mineral and rock collection

Predominantly quartz varieties, including amethyst, plus likely calcite, feldspar, mica, and miscellaneous polished stones

Hematite

Iron Oxide (Fe2O3)

Milky quartz vein fragment

Quartz (silicon dioxide, SiO₂), massive or granular variety

Quartz (Milky/Iron-stained)

Silicon Dioxide (SiO2)

Hematite

Iron(III) oxide (Fe2O3)

Orange calcite

Calcite (calcium carbonate, CaCO₃)

Hematite

Iron(III) oxide (Fe2O3)

Clear quartz crystal

Quartz (silicon dioxide, SiO₂), likely milky or included rock crystal

Quartz crystal

Quartz (silicon dioxide, SiO₂), possibly milky quartz

Milky quartz

Quartz (silicon dioxide, SiO₂)

Tumbled milky quartz pebble

Quartz (silicon dioxide, SiO₂)

Brecciated rock (possibly fault breccia)

Polymictic breccia; exact lithology cannot be determined from the photograph

Milky quartz fragment

Quartz (silicon dioxide, SiO₂)

Tumbled quartz (likely milky or included quartz)

Quartz, silicon dioxide (SiO₂)

Clear quartz

Quartz (silicon dioxide, SiO₂)

Quartz-rich rock fragment

Milky quartz, primarily silicon dioxide (SiO₂), possibly quartzite or a feldspar-bearing vein rock

Quartz fragment

Quartz (silicon dioxide, SiO₂)

Tumbled quartz-rich stone, likely milky quartz

Quartz (SiO₂), possibly iron-stained milky quartz or quartzite

Small quartz fragment (tentative)

Quartz, silicon dioxide (SiO₂)

Rounded quartz-rich pebble

Likely microcrystalline quartz (SiO₂), possibly milky quartz or a pale quartzite fragment

Mixed collection of minerals and rocks (Jasper, Carnelian, Granite, and Quartz)

Silicon Dioxide (SiO2) with varying impurities for silicates and igneous aggregates

Calcite specimen

Calcite (calcium carbonate, CaCO₃), likely pale blue-green massive or cleaved calcite with iron-oxide staining

Hematite

Iron(III) oxide (Fe2O3)

Clear quartz fragment

Quartz (silicon dioxide, SiO₂)

Pyrite

Iron Sulfide (FeS2)

Pyrite (Fool's Gold)

Iron Disulfide (FeS2)

Hematite

Iron(III) oxide (Fe2O3)

Pyrite

Iron Sulfide (FeS2)

Likely raw garnet fragment

Garnet-group silicate, commonly almandine (Fe₃Al₂Si₃O₁₂)

Small quartz crystal fragment (probable)

Quartz, silicon dioxide (SiO₂)

Rhodochrosite

Manganese Carbonate (MnCO3)

Quartz geode / druzy quartz

Quartz (SiO₂), likely a small chalcedony-lined geode with drusy quartz crystals

Quartz (Milky/Gray variety)

Silicon Dioxide (SiO2)