Sedimentary Rock (Altered)

Likely serpentinite (serpentine-rich rock)

Serpentine-group minerals, chiefly antigorite/lizardite; commonly derived from ultramafic peridotite

Rounded gray-green beach pebble

Likely basalt or fine-grained volcanic rock; exact identification requires testing

Greenstone pebble (likely serpentinite or altered basalt)

Serpentinite, predominantly serpentine-group minerals; exact identification requires testing

Gold-bearing sulfide ore (tentative)

Native gold, likely with pyrite/chalcopyrite in quartz or altered rock

Unakite

Altered Granite (Granitic Metamorphic Rock)

Greenstone / Serpentinite

Serpentine-group / Altered Mafic Rock

Unakite

Altered Granite (Granitic Metamorphic Rock)

Unakite

Altered Granite (Granitic Metamorphic Rock)

Weathered metamorphic outcrop, likely schist or gneiss

Undetermined foliated metamorphic rock; mineral composition cannot be confirmed from the photograph

Water-worn pebble, likely greenstone

Greenstone (metamorphosed mafic volcanic rock; commonly chlorite-, actinolite-, and epidote-bearing)

Amethyst

Silicon Dioxide (SiO2) with iron impurities

Quartz Vein in Greenstone

Metamorphic rock with quartz vein (SiO2 / mixed silicates)

Green serpentine (likely serpentine-rich stone)

Serpentine-group minerals, chiefly antigorite, lizardite, or chrysotile; composition approximately Mg₃Si₂O₅(OH)₄

Weathered greenstone / altered rock fragment

Probable chlorite–epidote–actinolite-rich metavolcanic rock; exact identification requires testing

Weathered greenstone (probable)

Chlorite–actinolite–epidote-rich metamorphosed mafic rock; exact identification requires testing

Porous limestone (likely coral limestone)

Calcite-rich carbonate rock; primarily calcium carbonate, CaCO₃

Dark, veined metamorphic rock (possibly gneiss or schist)

Undetermined from the photograph; likely a foliated, quartz-veined metamorphic rock

Likely tumbled basalt or dark river stone

Basalt; predominantly plagioclase and pyroxene, possibly with olivine

Weathered iron-rich metamorphic rock, possibly schist or metabasalt

Provisional identification: chlorite–quartz–feldspar schist or altered basalt; exact mineralogy requires testing

Tumbled ocean jasper or orbicular jasper

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

Dark igneous rock, likely basalt or diabase, with a second purplish specimen

Basalt/diabase; exact identification is uncertain from the photograph

Dalmatian jasper (often sold as Dalmatian stone)

Porphyritic alkali feldspar–quartz syenite, commonly with black arfvedsonite/aegirine-group amphibole inclusions

Serpentine

Serpentine-group (Mg, Fe, Ni, Al, Zn, Mn)2-3(Si, Al, Fe)2O5(OH)4

Likely greenstone (metamorphosed mafic rock)

Greenschist or altered basalt; exact identification is uncertain from the image

Greenstone (likely altered basalt or serpentinite)

Chlorite-rich metabasalt or serpentinite; exact identification requires testing

Unakite

Epidotized Granite

Tumbled greenstone-like pebble

Likely serpentine or chlorite-rich metamorphic rock; exact identification requires testing

Polished serpentine (likely green serpentine)

Serpentine-group minerals, chiefly antigorite, lizardite, or chrysotile; composition varies

Epidote

Epidote Group (Ca2(Al2,Fe3+)(SiO4)(Si2O7)O(OH))

Rounded volcanic pebble

Likely basaltic-andesite or altered basalt; exact identification requires testing

Rounded green-gray pebble, likely altered basalt

Fine-grained mafic volcanic rock; exact identification requires examination

Quartz-veined metamorphic rock, likely greenschist or altered metavolcanic

Chlorite–actinolite–epidote-bearing metavolcanic rock with quartz veins; exact identification requires testing

Unakite

Altered Granite (Epidotized Granite)

Likely raw mica-bearing metamorphic rock or mineral fragment

Tentatively biotite schist; visually similar dark mica-rich material

Greenstone (likely chlorite-rich metamorphic rock)

Chlorite schist/greenstone; possible actinolite- or epidote-bearing assemblage

Green-gray tumbled stone, possibly nephrite jade

Possible nephrite (interlocking tremolite–actinolite amphibole); identification is uncertain from the photograph

Weathered quartz-rich rock, possibly pegmatitic granite

Likely quartz–feldspar aggregate; exact identification requires testing

Serpentine

Serpentinite (Mg,Fe,Ni,Al,Zn,Mn)2-3(Si,Al,Fe)2O5(OH)4

Iron-rich jasper or hematite-bearing chert

Microcrystalline quartz (SiO₂) with hematite/goethite (Fe₂O₃/FeO(OH))

Amber (likely rough amber)

Fossilized plant resin; chiefly polymerized terpenoid resin (succinite, when Baltic-type)

Likely serpentinite

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

Banded chert or flint pebble

Microcrystalline quartz (SiO₂), likely chert with a pale weathered/altered zone