Mineraloid (Anthropogenic)

Ironstone concretion

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

Ironstone concretion (likely limonite/goethite-rich)

Iron-oxide/oxyhydroxide-rich concretion, chiefly goethite (FeO(OH)) and limonite; identification from the photo is provisional

Greenstone (likely altered basalt)

Metamorphosed mafic volcanic rock, commonly chlorite- and actinolite-rich; exact identification requires testing

Tumbled Dalmatian stone (Dalmatian jasper)

Trade name; commonly a leucocratic igneous rock with dark aegirine/arfvedsonite-group inclusions, often sold as “Dalmatian jasper”

Greenstone (likely altered basalt)

Greenschist-facies metabasalt; commonly composed of chlorite, actinolite, epidote, and albite

Yellow Jade (Serpentine/Quartz)

Silicate mineral aggregate

Polished green-gray stone, possibly serpentine

Likely serpentine-group rock, composed mainly of serpentine minerals; identification is uncertain from the photo

Tumbled basalt pebble

Basalt; fine-grained plagioclase feldspar and pyroxene, commonly with olivine and iron oxides

Weathered greenish-brown rock, likely serpentinized ultramafic rock

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

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

Likely basalt or dark mafic rock fragment

Basalt; primarily plagioclase feldspar and pyroxene, commonly with olivine and iron oxides

Tumbled goldstone-like quartz pebble

Likely iron-stained quartz or jasper; exact identification requires testing

Granite

Granite (phaneitic intrusive igneous rock)

Gneiss

Gneiss (High-grade regional metamorphic rock)

Granodiorite

Granodiorite (Intermediate intrusive igneous rock)

Granite Gneiss

Felsic Gneiss (composed of Quartz, Feldspar, and Biotite)

Diorite

Diorite (Intermediate intrusive igneous rock)

Porphyritic Basalt or Rhyolite Porphyry

Igneous porphyritic rock

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

Biotite-rich schist

Mica schist; predominantly biotite mica with quartz and feldspar

Tumbled yellow-green stone, likely serpentine

Serpentine-group minerals, commonly antigorite/lizardite (Mg₃Si₂O₅(OH)₄)

Gossan with Copper Carbonate (Chrysocolla/Malachite)

Ferruginous Oxide (Gossan) with Cu2CO3(OH)2 (Malachite) or (Cu,Al)2H2Si2O5(OH)4 (Chrysocolla)

Small rounded, foliated metamorphic pebble (likely greenschist)

Greenschist, commonly composed of chlorite, actinolite, and albite; exact identification requires testing

Pale-green schist fragment

Chlorite–sericite schist, possibly containing epidote or actinolite

Limonite with Quartz

FeO(OH)·nH2O (Limonite) with SiO2 (Quartz)

Granodiorite

Granodiorite (containing Plagioclase, Quartz, and Biotite)

Granitic Gneiss

Gneiss (High-grade metamorphic rock)

Granite

Phaneritic Plutonic Felsic Rock

Granite (Fine-grained)

Phaneritic Felsic Igneous Rock

Granite

Granite (Felsic Plutonic Rock)

Granite

Phaneritic Plutonic Igneous Rock (Granite)

Granite

Phaneritic Igneous Rock (composed of quartz, alkali feldspar, and plagioclase)

Granite

Felsic Intrusive Igneous Rock

Likely serpentinite

Serpentinite, composed mainly of serpentine-group minerals (e.g., antigorite, lizardite, or chrysotile)

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)

Weathered greenstone (metabasalt)

Chlorite–actinolite metabasalt; composition varies, commonly plagioclase with chlorite, actinolite, epidote, and amphibole

Tumbled dalmatian jasper (likely)

Trade name for a spotted, silica-rich rock; commonly quartz/chalcedony with dark inclusions, though this specimen may be another spotted feldspar-bearing stone