Sedimentary Rock (Altered)

Polished green banded stone, likely serpentine or altered greenstone

Probable serpentinite/greenstone; commonly dominated by serpentine-group minerals, chlorite, epidote, or actinolite

Lapis Lazuli

Na8(Al6Si6O24)S2 (Lazurite is the primary constituent mineral)

Rounded river cobble, likely basaltic rock

Fine-grained mafic volcanic rock, probably basalt or altered basalt

Puddingstone / orbicular jasper-like rock

Likely orbicular rhyolite or altered volcanic breccia, composed mainly of quartz, feldspar, and iron-bearing alteration minerals

Tumbled blue-green stone, likely chrysocolla-bearing jasper

Chrysocolla-rich chalcedony/jasper; commonly a mixture of chrysocolla (hydrated copper silicate, variable formula) and quartz (SiO₂)

Citrine Geode Fragment

Citrine (Silicon Dioxide with Iron Impurities), SiO2

Lapis Lazuli

Lazurite (primary mineral component), (Na,Ca)8(AlSiO4)6(S,SO4,Cl)1-2

Weathered basalt (likely altered basalt)

Basalt, chiefly plagioclase feldspar and pyroxene, with possible chlorite/epidote alteration

Tumbled red jasper

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

Tumbled greenstone (likely serpentine or chlorite-rich metamorphic rock)

Serpentinite, approximately Mg₃Si₂O₅(OH)₄, or chlorite-rich greenstone

Iron-rich vesicular rock, possibly weathered scoria or ironstone

Likely oxidized basaltic scoria (Fe-oxide-bearing volcanic rock); exact identification requires testing

Banded Jasper

Silicon Dioxide (SiO2)

Lapis Lazuli

Lapis Lazuli (Rock containing Lazurite: (Na,Ca)8(AlSiO4)6(S,Cl,SO4,OH)2)

Polished orbicular jasper (likely ocean jasper or leopard jasper)

Microcrystalline quartz (SiO₂) with iron-oxide pigments and altered volcanic inclusions

Red cabochon gemstone, likely carnelian

Carnelian: orange-red chalcedony, microcrystalline quartz (SiO₂)

Unakite (polished/tumbled)

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

Weathered quartz-rich rock, possibly granite or pegmatite fragment

Uncertain; likely quartz–feldspar aggregate, potentially granitic pegmatite

Pink-and-green granite or granitic gneiss

Coarse-grained granitoid, chiefly quartz, feldspar, and dark mafic minerals; pink areas likely potassium feldspar

Serpentinized ultramafic rock (likely serpentinite)

Serpentinite; chiefly serpentine-group minerals (chrysotile, lizardite, antigorite), with olivine/pyroxene relics and possible magnetite

Serpentine-rich ultramafic rock

Serpentinite (predominantly serpentine-group minerals: lizardite, chrysotile, and/or antigorite)

Lapis Lazuli

Lapis lazuli (Complex rock consisting mainly of Lazurite: (Na,Ca)8(AlSiO4)6(S,Cl,SO4,OH)2)

Tumbled green jasper (probable)

Jasper, opaque microcrystalline quartz (SiO₂), colored by iron and other impurities

Weathered sandstone or tuff fragment

Likely quartz-rich sandstone (SiO₂) or porous volcanic tuff; exact identification requires testing

Lapis Lazuli

Lazurite-rich metamorphic rock (approx. (Na,Ca)8(AlSiO4)6(S,Cl,SO4,OH)2)

Quartz on Greenstone

Silicon Dioxide (SiO2) on Altered Igneous Geologic Unit

Biotite granite pebble

Granite, chiefly quartz (SiO₂), feldspar, and biotite mica

Gray volcanic rock, likely basalt

Basalt; primarily plagioclase feldspar, pyroxene, and minor olivine/iron oxides

Tumbled pale limestone or calcite-rich stone

Limestone, chiefly calcite (CaCO₃); exact identification is uncertain from the photograph

Greenstone (likely serpentinite or chlorite-rich metamorphic rock)

Probable serpentinite/chlorite schist; commonly dominated by serpentine-group minerals, chlorite, talc, and magnetite

Blue-green copper mineralized rock, likely chrysocolla-bearing sandstone or copper ore

Chrysocolla (hydrated copper aluminosilicate; approximate formula (Cu,Al)₂H₂Si₂O₅(OH)₄·nH₂O), possibly with malachite and copper oxides in a sandstone host

Unakite

Unakitized granodiorite / Quartz-Epidote-Feldspar rock

Copper-bearing porphyritic rock (likely bornite/chalcopyrite ore)

Altered porphyritic volcanic rock with copper sulfides, chiefly bornite (Cu₅FeS₄) and/or chalcopyrite (CuFeS₂)

Polished greenstone (likely serpentinite or chlorite-rich schist)

Serpentinite/chlorite-rich ultramafic metamorphic rock; composition commonly dominated by serpentine-group minerals, chlorite, magnetite, and minor amphibole or pyroxene

Chalky limestone

Micritic limestone, primarily calcite (CaCO₃)

Bituminous coal

Coal; predominantly vitrinite and inertinite macerals composed chiefly of carbon, hydrogen, oxygen, nitrogen, and sulfur

Chrysocolla-bearing rock (likely chrysocolla in quartz/limonite matrix)

Chrysocolla, hydrated copper aluminosilicate: (Cu,Al)₂H₂Si₂O₅(OH)₄·nH₂O

Red vesicular volcanic rock, likely scoria

Scoria (vesicular basalt/andesite), composition mainly plagioclase, pyroxene, iron oxides, and volcanic glass

Porphyritic basalt (likely vesicular basalt)

Basalt, chiefly plagioclase feldspar and pyroxene, with possible olivine phenocrysts

Likely weathered basalt or mafic volcanic rock

Basalt; chiefly plagioclase feldspar, pyroxene, and commonly olivine or iron oxides

Weathered quartz-rich rock fragment

Indeterminate; likely altered granite or quartz-bearing pegmatite

Pale green rounded boulder, likely altered serpentinite or greenstone

Probable serpentinized ultramafic rock; exact identification requires testing

Iron-rich weathered rock, possibly limonite/goethite-bearing laterite

Limonite (amorphous hydrated iron oxides), commonly mixed with goethite (α-FeO(OH)) and hematite