Mineraloid

Granite Cobble

Plutonic Granite

Graphite Schist

C (Carbonaceous Schist)

Possible green tourmaline (small rough crystal fragment)

Possibly elbaite, Na(Li₁.₅Al₁.₅)Al₆(Si₆O₁₈)(BO₃)₃(OH)₄; identification is uncertain from the blurry image

Raw ruby (likely corundum)

Corundum, Al₂O₃; red varieties are ruby

Cat's Eye Moonstone (Feldspar)

Orthoclase (KAlSi3O8) with Albite (NaAlSi3O8) inclusions

Small blue-green mineral or stone bead

Unidentified opaque blue-green mineral; the image is insufficient for reliable species identification

Small tumbled stone, likely quartz-rich pebble

Probably microcrystalline quartz (SiO₂), but the image is insufficient for a definitive identification

Small rounded stone or mineral fragment

Indeterminate; likely a common quartz- or feldspar-bearing silicate fragment

Ironstone concretion (possibly a pyrite-bearing concretion)

Iron-oxide-cemented sedimentary concretion; exact mineral composition cannot be confirmed from the photograph

Bismuth crystal

Bismuth (Bi), commonly laboratory-grown

Polished amber

Fossilized tree resin (primarily organic polymerized diterpenes)

Hag Stone

Sandstone or Limestone with Solution Holes (Bioturbation/Erosion)

Banded Calcite (Mexican Onyx)

Calcium Carbonate (CaCO3)

Blue-dyed tumbled stone, likely howlite or magnesite

Likely dyed magnesite (MgCO₃) or howlite (Ca₂B₅SiO₉(OH)₅); identification is uncertain from the image

Greenstone / Glauconitic Siltstone

Metabasalt or Glauconite-rich Sedimentary Rock

Unidentified purple mineral fragment

Possibly amethyst (quartz), but the image is insufficient for confident identification

Serpentinite

Serpentinite, a rock composed mainly of serpentine-group minerals (approximately Mg₃Si₂O₅(OH)₄)

Tumbled serpentine (likely nephrite-like greenstone)

Serpentine-group minerals, chiefly antigorite/lizardite; possibly mixed with tremolite-actinolite

Tumbled serpentine or chlorite-rich pebble

Serpentine-group minerals, chiefly antigorite/lizardite; possibly chlorite or greenstone

Optical Calcite (Iceland Spar)

Calcite (Calcium Carbonate, CaCO3)

Limestone or Sandstone Cobble

Sedimentary rock (Calcium carbonate or Quartz based)

Weathered greenish-brown rock, likely serpentinized ultramafic rock

Serpentinite; chiefly serpentine-group minerals (Mg₃Si₂O₅(OH)₄), possibly with olivine, pyroxene, magnetite, or carbonate

Rounded iron-rich pebble

Likely ferruginous sandstone or ironstone; exact identification requires testing

Osumilite in Granite Matrix

(K,Na)(Fe,Mg)2(Al,Fe)3(Si,Al)12O30

Granite (Alkali-feldspar Granite)

Felsic Plutonic Rock (Primary minerals: Quartz SiO2, Orthoclase KAlSi3O8, Plagioclase (Na,Ca)AlSi3O8)

Basalt with Plagioclase Phenocrysts

Porphyritic Basalt

Pink Granite

Granite (Phaneritic intrusive igneous rock)

Quartzite

Quartzite (primarily SiO2)

Granite (with Orthoclase and Quartz)

Phaneritic Felsic Igneous Rock (KAlSi3O8 + SiO2)

Ironstone concretion

Iron-oxide-cemented sediment, chiefly goethite (α-FeO(OH)) and/or hematite (Fe₂O₃)

Iron Slag

Iron smelting byproduct (Glassy/vesicular silicate)

Potassium feldspar

Orthoclase or microcline; KAlSi₃O₈

Serpentinized ultramafic rock (serpentinite)

Serpentinite; chiefly serpentine-group minerals, Mg₃Si₂O₅(OH)₄, with possible magnetite, olivine, pyroxene, and brucite

Tumbled green aventurine (probable)

Quartz, SiO₂, with fuchsite mica inclusions

Mixed River Pebbles

Clastic Sedimentary Alluvial Deposit / Polymictic Conglomerate Clasts

Painite

Painite, CaZrAl₉O₁₅(BO₃)

Copper-bearing rock, likely native copper in a weathered matrix

Native copper (Cu), tentatively with copper sulfide/oxide minerals

Tumbled dark green stone, likely serpentine

Serpentinite; chiefly serpentine-group minerals (Mg₃Si₂O₅(OH)₄)

Graphite-bearing quartz-mica schist

Graphite-rich quartz–mica schist; primarily quartz (SiO₂), muscovite/biotite, and graphite (C)

Blue glass-like tumbled specimen

Most likely cobalt-blue slag glass or manufactured glass; not confidently identifiable as a natural mineral from the image

Serpentine-rich rock (likely antigorite serpentinite)

Serpentinite, composed mainly of serpentine-group minerals such as antigorite, lizardite, or chrysotile

Polished dark-blue cabochon, possibly blue sodalite

Undetermined; blue sodalite is a possible identification (Na₈Al₆Si₆O₂₄Cl₂)