Anthropogenic Material

Sea Glass (specifically Frosted White)

Amorphous Silica (substance: Sodium-calcium silicate glass)

Iron Slag

Vitreous glassy waste (Fe-Si-Al-Ca compounds)

Petrified Wood

Silicified Wood (SiO2)

Quartz-veined metamorphic cobble

Likely quartzite or quartz-rich metasedimentary rock; veins predominantly quartz (SiO₂)

Dendritic jasper (brecciated or orbicular jasper)

Microcrystalline quartz (SiO₂) with iron-oxide inclusions

Weathered quartz-rich rock, possibly quartzite or chert

Quartz (SiO₂), likely in a quartzite matrix; exact identification is uncertain from the image

Biotite-rich schist with garnet-like inclusion

Mica schist; predominantly muscovite/biotite mica, quartz, and feldspar, with a possible garnet or weathered mafic fragment

Basalt (Vesicular)

Extrusive mafic igneous rock; primarily (Mg, Fe)2SiO4 (Olivine), CaAl2Si2O8 (Plagioclase Feldspar), and Pyroxene

Sandstone Clast

Arenite (primarily SiO2)

Coquina

Biogenic Limestone (Coquina)

River Siltstone / Mudstone Pebble

Siltstone (composed of mixed silicate and carbonate minerals)

Petrified Wood

Silicified Wood (SiO2)

Serpentinite with green serpentine inclusion

Serpentinite; serpentine-group minerals, chiefly antigorite, lizardite, or chrysotile, with possible magnetite

Red jasper flake/tool blank

Jasper, microcrystalline quartz (SiO₂), colored by iron oxides

Slag (Industrial Byproduct)

Ferro-silicate glass (Slag)

Green Sea Glass

Amorphous Silica (man-made glass), SiO2 + additive metal oxides

Goldfish Cracker (Culinary Mimic)

Cibus aurum (Commonly composed of Enriched Wheat Flour and Cheddar Cheese)

Sea Glass (Uranium/Vaseline Glass variant)

Silicon Dioxide (SiO2) with trace Uranium Oxide (U3O8)

Iron-rich concretion or weathered ironstone pebble

Goethite/limonite-bearing ironstone; commonly an iron-oxide concretion (FeO(OH)·nH₂O, variable)

Slate

Slate (Foliated metamorphic rock)

Tumbled blue-dyed stone, likely basalt or blue aventurine

Likely fine-grained basalt (plagioclase and pyroxene), possibly coated or dyed; exact identification requires testing

Chert (Arrowhead Fragment)

Cryptocrystalline quartz (SiO2)

Tumbled quartz or chalcedony (uncertain)

Quartz, SiO₂; possibly cryptocrystalline chalcedony

Milky Quartz

Silicon Dioxide (SiO2)

Quartz Pebble

Silicon Dioxide (SiO2)

Sandstone

Clastic sedimentary rock (Quartz arenite / Arkose)

Schist

Mica Schist

Coquina

Coquina (Bioclastic Limestone)

Sea Glass

Man-made vitreous material

Tumbled tiger’s eye

Quartz (SiO₂) with fibrous riebeckite/crocidolite inclusions

Diamond

C

Chert (Flint)

Sedimentary Cryptocrystalline Quartz (SiO2)

Diamond (or Diamond Simulant like Cubic Zirconia)

Carbon (C) - if Diamond; Zirconium dioxide (ZrO2) - if Cubic Zirconia

Glass

Amorphous Silicon Dioxide (SiO2)

Goldstone

Aventurine Glass (Man-made)

Ferruginous Sandstone (Ironstone Conglomerate fragments)

Ferruginous clastic sedimentary rock (SiO2 cemented by Fe2O3)

Zebra Jasper

Tetragonal Silicon Dioxide (Quartz) with impurities

Polished Porcelain Jasper

Jasper (microcrystalline quartz, SiO₂), commonly sold as Porcelain Jasper

Engineered Quartz

Engineered Stone (primarily SiO2)

Iron-rich sandstone or weathered laterite

Ferruginous sandstone, composed mainly of quartz with iron-oxide cement (Fe₂O₃/FeOOH)

Quartzite

Quartzite

Weathered quartz-rich rock, possibly quartzite or silicified sandstone

Quartzite (predominantly microcrystalline quartz, SiO₂); precise identification requires testing