Metamorphic Or Igneous Alteration

Tumbled green-yellow stone, likely serpentine or nephrite jade

Serpentine-group mineral aggregate, commonly lizardite/antigorite; possible nephrite (interlocking tremolite-actinolite)

Tumbled greenstone (likely serpentine or nephrite jade)

Serpentine-group mineral aggregate, or possibly nephrite (interlocking tremolite–actinolite amphibole)

Quartz vein in weathered host rock

Quartz (SiO₂), likely in a weathered metamorphic or igneous matrix

Banded gneiss (likely biotite-bearing)

Gneiss; quartz–feldspar–mica assemblage, with possible iron-oxide staining

Perlite (Unexpanded)

Amorphous volcanic glass

Polished rhodonite

Rhodonite, manganese inosilicate (MnSiO₃), commonly mixed with quartz and manganese oxides

Rhyolite (likely porphyritic)

Rhyolite; chiefly quartz, alkali feldspar, plagioclase, and volcanic glass, with possible iron-oxide staining

Tumbled greenstone (likely serpentine)

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

Greenish altered rock, possibly serpentinite or chlorite-rich schist

Tentative: serpentine-group minerals, chiefly antigorite/lizardite, or chlorite–actinolite assemblage

Green serpentine or nephrite-like stone

Serpentinite, chiefly serpentine-group minerals; exact identification would require testing

Green Aventurine

Silicon Dioxide (SiO2) with Fuchsite inclusions

Tiger's Eye

Pseudomorph of Quartz after Crocidolite (SiO2 with iron oxide inclusions)

Tumbled serpentine

Serpentinite; chiefly antigorite, lizardite, and/or chrysotile-group minerals

Iron-stained metamorphic rock, likely schist or quartzite

Quartz–mica–iron oxide rock; probable muscovite/biotite schist or ferruginous quartzite

Unakite

Altered Granite (Granitic Metamorphic Rock)

Glacial Granite with Epidote

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

Rounded greenstone pebble

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

Likely serpentine or serpentinite

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

Greenstone, possibly serpentine or altered basalt

Serpentinite (Mg₃Si₂O₅(OH)₄) or chlorite-epidote altered basalt; identification is uncertain from the image

Weathered greenstone

Metamorphosed mafic rock, commonly chlorite–actinolite schist or altered basalt

Unakite-like jasper / epidote–feldspar rock

Epidote–feldspar–quartz aggregate; commonly marketed as unakite or brecciated jasper

Tumbled greenstone/chlorite-rich pebble

Likely chlorite-rich greenschist or altered basalt; exact identification requires testing

Quartz-rich rock with chlorite/epidote vein

Milky quartz with green chlorite or epidote; exact identification requires testing

Soapstone (Steatite)

Steatite (primarily Talc: Mg3Si4O10(OH)2)

Epidote

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

Weathered gray stone, possibly basalt or granitic rock

Indeterminate fine- to medium-grained silicate rock; possible basalt, diabase, or weathered granite

Rounded greenish volcanic pebble, likely andesite

Fine-grained andesite (tentative; exact identification requires closer examination)

Serpentine

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

Serpentinite

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

Serpentinite

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

Unakite

Unakite (altered granitic rock)

Greenstone, likely altered basalt (possibly serpentinite)

Metabasalt/greenschist; commonly chlorite–actinolite–epidote ± serpentine

Sodalite

Na8(Al6Si6O24)Cl2

Unakite (polished/tumbled)

Unakite, a hydrothermally altered granite composed mainly of epidote, pink potassium feldspar (orthoclase/microcline), and quartz

Granite (with alteration)

Granite (Felsic intrusive igneous rock)

Green nephrite jade, polished egg-shaped specimen

Nephrite jade: interlocking tremolite–actinolite amphibole, Ca₂(Mg,Fe)₅Si₈O₂₂(OH)₂

Tumbled greenstone (likely serpentine or nephrite-like material)

Serpentine-group minerals, commonly antigorite/lizardite; possibly nephrite jade (actinolite-tremolite)

Likely greenstone (metamorphosed basalt)

Greenschist or chlorite–epidote altered basalt; commonly composed of chlorite, epidote, actinolite, albite, and quartz

Tumbled serpentine

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

Serpentinite (probable)

Serpentinite, dominated by serpentine-group minerals (Mg₃Si₂O₅(OH)₄), with dark magnetite or chromite and pale carbonate/talc possible

Polished nephrite jade

Nephrite jade — interlocking amphibole, chiefly tremolite–actinolite, Ca₂(Mg,Fe)₅Si₈O₂₂(OH)₂

Ruby

Corundum (Al2O3:Cr)