Mineral Or Sedimentary Rock (With Mineral Inclusions)

Iron-stained quartz fragment (probable quartzite or chert)

Quartz, SiO₂; possibly iron-oxide-stained microcrystalline silica

Mexican Crazy Lace Agate

Silicon Dioxide (SiO2) with iron and aluminum inclusions

Milky Quartz Vein in Host Rock

Silicon Dioxide (SiO2)

Yellow Quartz (Citrine Quartz variety / Ferruginous Quartz)

Silicon Dioxide (SiO2) with iron inclusions

Quartz (Milky Quartz)

Quartz (Silicon Dioxide, SiO2)

Vesicular Basalt (Amygdaloidal Basalt)

Basalt with Secondary Mineral Inclusions

Moss Agate

Silicon Dioxide (SiO2) with inclusions of Manganese or Iron oxides

Sandstone (Micaceous Sandstone)

Arenite (SiO2 with KAl2(AlSi3O10)(OH)2 inclusions)

Herkimer Diamond (Quartz)

Silicon Dioxide (SiO2)

Weathered stone, likely sandstone or altered volcanic rock

Indeterminate; possibly quartz-rich sandstone or weathered tuff

Weathered sedimentary rock, possibly sandstone

Indeterminate clastic sediment; probable quartz-rich sandstone

Sandstone (Iron-stained)

Quartz Arenite with Iron Oxide Stain (SiO2 + Fe2O3)

Polished red jasper

Jasper, an opaque microcrystalline variety of quartz (SiO₂), colored mainly by iron oxides

Amygdaloidal Basalt

Amygdaloidal Basalt containing Zeolite and Calcite inclusions

Unidentifiable Specimen

Undetermined

Sandstone (likely Graywacke or Lithic Arenite)

Clastic sedimentary rock predominantly composed of silicate grains

Sandstone

Arenite

Yellow chalcedony or quartz fragment

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

Mica Schist

Mica Schist (predominantly Muscovite or Biotite sheet silicates)

Red Quartz (Druzy)

Silicon Dioxide (SiO2) with Hematite inclusions

Pink halite (rock salt)

Halite — sodium chloride (NaCl), likely colored by impurities or inclusions

Milky Quartz Pebbles

Silicon Dioxide (SiO2)

Quartz-rich rock, possibly milky quartz with chlorite or epidote

Quartz (SiO₂), with unidentified green inclusions

Yellow Quartz Pebble

Silicon Dioxide (SiO2)

Quartz (Milky Quartz)

Silicon Dioxide (SiO2)

Bumblebee Jasper

Carbonate-rich volcanic rock containing Sulfur and Arsenic (Realgar/Orpiment)

Tumbled jasper or brecciated jasper

Microcrystalline quartz (chalcedony), SiO₂, with iron-oxide and dark mineral inclusions

Quartz-bearing rock or quartz-rich mineral specimen

Quartz, silicon dioxide (SiO₂); exact host rock is uncertain from the image

Sandstone

Clastic sedimentary rock (quartz arenite)

Chalcedony (Agate)

Quartz (Silicon Dioxide, SiO2)

Mica Schist (with Muscovite mica)

Mica Schist (KAl2(AlSi3O10)(OH)2)

Chert (Jasper)

Microcrystalline Quartz (SiO2)

Quartz (Milky Quartz)

Silicon Dioxide (SiO₂)

Blue-gray quartz-bearing rock, likely rough chalcedony or silicified host rock

Microcrystalline quartz (SiO₂), possibly with iron-oxide staining and minor feldspar/clay minerals

Sandstone

Arenite (primarily Quartz Arenite)

Dalmatian Jasper

Peralkaline Rhyolite (composed of Quartz, Feldspar, and Arfvedsonite)

Quartz (Herkimer Diamond variant)

Silicon Dioxide (SiO2)

Quartz-rich rock, likely milky quartz with iron staining

Quartz (SiO₂), possibly quartzite or quartz vein material

Tumbled ocean jasper or orbicular jasper

Microcrystalline quartz (SiO₂), commonly with chalcedony, feldspar, and iron-oxide inclusions

Yellow Jasper

Silicon Dioxide (SiO2) with Iron Hydroxide impurities

Red Sandstone

Ferruginous Sandstone (formula varies, primarily SiO2 with Fe2O3)

Dendritic Agate (specifically Orange/Tumbled)

Silicon Dioxide (SiO2) with Oxide Inclusions