Sedimentary Rock (Altered)

Pink-gray granite

Granite; primarily quartz, potassium feldspar, plagioclase, and biotite/hornblende

Porphyritic basalt or weathered volcanic rock

Basalt, likely plagioclase–pyroxene rock with possible olivine; exact identification requires testing

Greenstone (River Pebble)

Metabasalt / Greenschist

Polished serpentine (likely green serpentinite)

Serpentinite; chiefly serpentine-group minerals, Mg₃Si₂O₅(OH)₄, with magnetite and possible chromite or carbonate inclusions

Chrysocolla-bearing copper mineral specimen (probable turquoise/chrysocolla mix)

Chrysocolla, Cu₂H₂Si₂O₅(OH)₄·nH₂O, with possible turquoise CuAl₆(PO₄)₄(OH)₈·4H₂O and copper oxides

Weathered basaltic cobble

Altered basalt, predominantly plagioclase and pyroxene

Likely granite or granitic gneiss

Quartz–feldspar–mica rock; exact identification requires closer inspection

River Cobble (likely Metasedimentary or Basalt)

Metamorphosed Siltstone or Altered Fine-grained Igneous Rock

Ruby in Zoisite

Anyolite

Weathered vesicular basalt

Basalt, a mafic volcanic rock composed mainly of plagioclase feldspar, pyroxene, and commonly olivine

Brecciated jasper, possibly rainforest jasper or brecciated rhyolite

Brecciated microcrystalline quartz (SiO₂), commonly called jasper; the green portions may contain epidote, chlorite, or iron-bearing silicates, while red-brown areas are typically hematite or other iron oxides

Iron-oxide-stained quartz-rich rock (likely ironstone or ferruginous quartzite)

Ferruginous quartzite; predominantly quartz (SiO₂) with iron oxides/hydroxides such as hematite and goethite

Likely granite or granitic gneiss

Granite: coarse-grained felsic intrusive rock, typically quartz, potassium feldspar, plagioclase, and mica; the image alone cannot distinguish it confidently from gneiss.

Weathered iron-rich sandstone or siltstone

Clastic siliciclastic sedimentary rock, likely ferruginous sandstone/siltstone (quartz-rich, Fe-oxide cement)

Weathered porphyritic volcanic rock (likely andesite or basalt)

Aphanitic to porphyritic andesite–basalt; composition commonly plagioclase, pyroxene, and minor iron oxides

Weathered granite or granitic gneiss

Granite; primarily quartz, feldspar, and mica (possibly foliated as gneiss)

Serpentine

Antigorite, Lizardite, or Chrysotile; (Mg,Fe,Ni,Al,Zn,Mn)2-3(Si,Al,Fe)2O5(OH)4

Serpentine-rich breccia (possibly listvenite)

Serpentinite breccia, with carbonate and quartz veins; exact identification requires testing

Quartz–pyrite-bearing vein rock, possibly gold-bearing

Quartz (SiO₂) with iron sulfides, chiefly pyrite (FeS₂), in altered host rock

Weathered copper-bearing rock (likely malachite-stained basalt or greenstone)

Malachite, Cu₂CO₃(OH)₂, as a secondary coating on a mafic host rock; exact identification requires testing

Possibly polished black tourmaline (small cut stone)

Tourmaline-group mineral, likely schorl; complex borosilicate, approximately NaFe₃Al₆(BO₃)₃Si₆O₁₈(OH)₄

Quartz geode/drusy quartz cluster

Quartz (SiO₂), with probable feldspar host and minor iron-oxide staining

Orbicular jasper (likely ocean or leopard jasper)

Siliceous microcrystalline quartz aggregate; mainly SiO₂ with iron oxides and accessory feldspar/carbonates

Polished orbicular jasper (likely kambaba jasper)

Kambaba jasper; cryptocrystalline quartz/chalcedony with dark green and gray orbicular aggregates, commonly associated with altered volcanic material

Lapis Lazuli

Na8[Al6Si6O24]Sn (Lazurite-rich metamorphic rock)

Tumbled tiger’s-eye-rich quartzite

Quartzite, composed mainly of microcrystalline quartz (SiO₂) with fibrous crocidolite pseudomorphs and iron oxides

Weathered granite or granitic gneiss

Granite; predominantly quartz, feldspar, and mica, possibly altered to gneiss

Unakite

Unakite, an epidote-altered granite composed mainly of epidote, pink orthoclase feldspar, and quartz

Pink Granite / Gneiss Pebble

Quartz-Feldspar Granitic Rock

Likely gray-green metamorphic rock fragment

Unidentified fine-grained metamorphic rock; exact identification is not possible from this small image

Fossil Coral

Coral Limestone (a type of biogenic sedimentary rock)

Likely coal (possibly anthracite)

Coal, composed chiefly of carbon-rich organic matter; rank cannot be confirmed from the photograph

Blue calcite

Calcite (CaCO₃)

Likely greenstone (metamorphosed basalt)

Metabasalt; commonly composed of chlorite, actinolite, epidote, and albite

Jasper

Microcrystalline Quartz (SiO2)

Jasper

Microcrystalline Quartz (SiO2)

Jasper

Microcrystalline Quartz (SiO2)

Green-and-black serpentine-rich rock

Serpentinite, likely with magnetite and chlorite/pyroxene

Granite (weathered fragment)

Granite; chiefly quartz, alkali feldspar, plagioclase, and mica

Quartz-rich rock, possibly yellow chalcedony or weathered quartzite

Quartz (SiO₂), likely microcrystalline chalcedony with iron-oxide staining

Iron-stained quartzite or silicified breccia

Quartz-rich rock dominated by microcrystalline quartz (SiO₂), with iron oxides/hydroxides such as hematite and goethite

Yellow-green jasper or serpentine-rich rock

Likely microcrystalline quartz (SiO₂) with iron-bearing and/or serpentine minerals; exact identification requires testing