Sedimentary Rock (Altered)

Serpentinite

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

Gray-green rough stone, possibly serpentinite

Indeterminate from the photograph; possible serpentinite, a rock composed mainly of serpentine-group minerals

Weathered greenstone (likely serpentinite or altered basalt)

Serpentinite-group rock, commonly dominated by serpentine minerals (antigorite/lizardite); exact identification requires testing

Tumbled pale greenish stone, likely serpentine or altered limestone

Probable serpentine-group rock (antigorite/lizardite), possibly serpentinite; identification is visual only

Likely mafic metamorphic rock with sulfide mineralization

Probable amphibolite or hornblende–biotite schist, locally bearing pyrite/other sulfides

Green Opal (Prase Opal)

SiO2 · nH2O (Hydrated Silicon Dioxide)

Greenstone / Greenschist

Greenschist (composed of Chlorite, Epidote, Actinolite)

Serpentine

Serpentine group, including Antigorite, Lizardite, and Chrysotile (Mg,Fe,Ni,Al,Zn,Mn)2-3(Si,Al,Fe)2O5(OH)4

Greenstone / altered mafic rock

Likely chlorite–epidote–actinolite schist or altered basalt (greenstone); exact identification requires thin-section or chemical testing.

Unakite

Altered Granite (Epidotized Granite)

Lapis Lazuli

Lazurite-dominated contact metamorphic rock

Iron-rich metamorphic rock, likely schist or gneiss

Possibly biotite–chlorite schist or iron-stained gneiss; exact identification requires closer examination

Iron-stained quartz-rich rock

Likely quartz with iron oxides/hydroxides (goethite and/or limonite); exact rock type cannot be determined from the image

Tumbled greenstone, likely serpentine or altered basalt

Serpentine-group minerals, chiefly Mg₃Si₂O₅(OH)₄; possibly chlorite/epidote-bearing mafic rock

Green-speckled igneous rock, likely epidote-bearing basalt or serpentinite

Tentatively epidote-bearing basalt (compositionally uncertain from the image)

Weathered pink-gray granite or granitic gneiss

Felsic granitoid; primarily quartz, K-feldspar, plagioclase, and minor biotite/hornblende

Weathered basalt (likely vesicular basalt)

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

Yellow serpentine (likely lemon chrysoprase/serpentine breccia)

Serpentine-group minerals, chiefly antigorite/lizardite; commonly mixed with magnesite and iron oxides

Unakite

Altered Granite (Epidotized Granite)

Leopard jasper (orbicular jasper)

Silicified volcanic rock, chiefly microcrystalline quartz/chalcedony (SiO₂) with feldspar and iron-oxide inclusions

Dark green-gray river-worn rock, likely serpentinite

Serpentinite (rock composed chiefly of serpentine-group minerals; identification is provisional from the photograph)

Fine-grained green-gray pebble, likely andesite

Probable andesite (plagioclase-rich volcanic rock; exact identification needs close examination)

Turquoise (small irregular fragment)

Turquoise, hydrated copper aluminum phosphate: CuAl₆(PO₄)₄(OH)₈·4H₂O

Serpentine / Serpentinite (with Weathering Crust)

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

Tumbled greenstone (likely serpentine-rich)

Serpentinite or chlorite/epidote-rich greenstone; exact identification requires testing

Serpentine-rich altered rock

Serpentinite, likely with chlorite and magnetite; exact identification requires testing

Likely greenstone (serpentinized ultramafic rock)

Serpentinite, dominated by serpentine-group minerals (chrysotile/lizardite/antigorite), possibly with chlorite or epidote

Weathered vesicular basalt (likely amygdaloidal basalt)

Basalt, chiefly plagioclase + pyroxene ± olivine; cavities may contain secondary zeolites, calcite, or chlorite

Serpentinite

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

Weathered greenish metamorphic rock, possibly serpentinite

Serpentinite; chiefly serpentine-group minerals, commonly Mg₃Si₂O₅(OH)₄, with possible magnetite and chlorite

Quartz vein rock

Milky quartz (SiO₂) in altered host rock, likely quartz-bearing hydrothermal breccia

Tumbled jasper, likely brecciated or brown-green jasper

Microcrystalline quartz (chalcedony), SiO₂, with iron-oxide and other mineral impurities

Greenstone Porphyry

Altered Porphyritic Andesite/Basalt

Weathered greenstone (likely serpentinite or altered basalt)

Serpentinite, primarily Mg-rich serpentine minerals; possibly chlorite/actinolite-bearing altered mafic rock

Greenish weathered volcanic rock, likely altered basalt

Altered basalt/mafic volcanic rock; green coloration may reflect chlorite, epidote, or celadonite

Tiger's Eye

Silicon Dioxide with Crocidolite (SiO2)

Lapis Lazuli

Complex rock primarily containing Lazurite (Na,Ca)8(AlSiO4)6(S,Cl,SO4,OH)2

Unakite

Unakite (metamorphosed granite)

Porphyritic basalt or andesite pebble

Porphyritic volcanic rock; commonly plagioclase phenocrysts in a fine mafic-to-intermediate matrix

Rounded porphyritic volcanic rock, likely andesite or basalt

Porphyritic andesite–basalt; composition commonly plagioclase, pyroxene, and iron-magnesium minerals

Reddish weathered rock, likely iron-rich basalt or jasper

Probable basalt (mafic silicate rock) with hematite/goethite staining; exact identification requires testing

Tumbled jasper or chert

Microcrystalline quartz (SiO₂), likely iron-stained jasper/chert