Industrial Byproduct (Anthropogenic Rock)

Tumbled White Quartz

Silicon Dioxide (SiO2)

Rounded brown pebble, likely quartz-rich river stone

Indeterminate lithic pebble; possibly iron-stained quartzite or chert

Polished brecciated jasper (likely)

Brecciated jasper, an opaque microcrystalline quartz (SiO₂) with contrasting silica-rich fragments and matrix

Quartz Vein Rock

Silicon Dioxide (SiO2)

Agate

Silicon Dioxide (SiO2)

Small rounded pebble, likely porous volcanic rock

Possibly vesicular basalt or scoria; exact identification is not possible from the image alone

Purple glassy pebble, possibly slag glass

Unidentified; likely man-made glass rather than a natural mineral

Limestone

Calcium carbonate (CaCO3)

Small gray-green pebble (likely fine-grained volcanic rock)

Indeterminate; possibly andesite or basalt

Quartz Geode

Silicon Dioxide (SiO2)

Weathered quartz-bearing rock, possibly calcite vein fragment

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

Quartz Druzy (Geode Fragment)

Silicon Dioxide (SiO2)

Sandstone with Concretions / Liesegang Rings

Arenite with iron oxide banding

Wavellite with Quartz

Al3(PO4)2(OH,F)3 & SiO2

Unknown dark mineral fragment

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

Sandstone Cobble with Iron Staining

Arenite with Limonite/Hematite staining

River Stone (likely Basalt or Greywacke)

Basalt with mineral veining

Basalt (Weathered)

Mafic Igneous Rock

Pegmatite (Quartz, Feldspar, and Tourmaline/Biotite)

Pegmatitic Igneous Rock

Agate

Silicon dioxide, SiO2

Small iron-stained pebble

Likely iron-oxide-stained quartz-rich rock; exact identification is not possible from the image alone

Rounded river pebble, likely sandstone or quartzite

Unidentified silicate-rich pebble; visual appearance is consistent with sandstone, but quartzite is also possible

Iron-rich meteorite candidate

Unclassified meteoritic iron–stone material; possible stony-iron meteorite or terrestrial ironstone

Polished brecciated jasper

Microcrystalline quartz (SiO₂), with iron-oxide staining

Rounded brown pebble

Unidentified lithic pebble; composition cannot be determined from the image

Basalt

Mafic volcanic rock

Basalt River Stone

Basaltic Igneous Rock

Quartz Pebble

Silicon Dioxide (SiO2)

Basalt

Basalt

Granodiorite

Granodiorite

Milky Quartz Nodule / Geode precursor

Silicon Dioxide (SiO2)

Sandstone with Iron Concretion

Arenite with Limonite/Goethite Concretion

Carved pyrite frog or toad

Pyrite (iron disulfide, FeS₂), likely a carved massive aggregate

Quartz Druzy (Geode Fragment)

Silicon Dioxide (SiO2)

Native Copper Bearing Basalt

Cu

Quartz Geode

Silicon Dioxide (SiO2)

Quartz Geode

Silicon Dioxide (SiO2)

Rounded gray river cobble, likely quartz-rich sandstone or weathered granite

Indeterminate; possible granitic or feldspathic cobble (quartz–feldspar–mica aggregate)

Graywacke

Lithic Sandstone (Graywacke)

Small weathered rock fragment

Unidentified iron-stained, fine-grained rock; exact composition cannot be determined from the image

Quartz (Gravel Fragment)

Silicon Dioxide (SiO2)

Tumbled brecciated jasper (likely ocean or mahogany jasper)

Jasper—microcrystalline quartz/chalcedony, SiO₂, with iron-oxide inclusions