Mineraloid

Quartzite

Metamorphosed Quartz Sandstone (SiO2)

Banded slate or phyllite

Fine-grained foliated metasedimentary rock; likely slate with light-colored quartz veins

Fossil ammonite

Ammonoidea; likely a chambered ammonite mold/cast

Weathered volcanic rock fragment

Indeterminate fine-grained mafic-to-intermediate igneous rock; possibly andesite or basalt

Weathered sandstone pebble

Quartz-rich sandstone, likely iron-oxide-stained (SiO₂-dominant)

Rounded river pebble, likely quartz-rich sandstone or weathered quartzite

Indeterminate; probable quartz (SiO₂)-rich clastic rock

Greenstone pebble

Likely chlorite- or epidote-bearing metamafic rock (metabasalt/greenschist)

Probable weathered basalt or andesite

Fine-grained mafic to intermediate volcanic rock; commonly plagioclase ± pyroxene, amphibole, and iron oxides

Granite

Felsic intrusive igneous rock

Weathered porphyritic volcanic rock

Likely andesite or dacite, with feldspar phenocrysts in a fine-grained groundmass

Sandstone (Quartzose Sandstone)

Arenite (primarily SiO2 with minor Fe2O3)

Green tourmaline (verdite-like rough)

Likely elbaite, Na(Li₁.₅Al₁.₅)Al₆(Si₆O₁₈)(BO₃)₃(OH)₄; identification from the photo is tentative

Greenstone with rusty mineral patches

Greenstone (metamorphosed mafic volcanic rock; likely chlorite–epidote–actinolite assemblage)

Raw green calcite (likely)

Calcite, calcium carbonate (CaCO₃)

Polished septarian nodule

Septarian concretion, commonly calcite/aragonite with brown iron-oxide or siderite veins in a clay-rich matrix

Sandstone

Clastic sedimentary rock (primarily SiO2)

Weathered iron-rich rock, possibly limonite-bearing sandstone or laterite

Limonite/goethite mixture (hydrated iron oxides), composition uncertain from image

Granite (Dioritic or Hornblende-rich)

Phaneritic Plutonic Felsic to Intermediate Igneous Rock

Likely hornblende-rich amphibolite

Amphibolite, composed chiefly of hornblende (amphibole) and plagioclase feldspar

Quartz-veined metamorphic rock, likely quartzite or schist

Quartz-rich metamorphic rock with a milky-quartz vein; exact host rock is indeterminate from the photo

Granite-like pegmatitic rock

Coarse-grained granite or granitic pegmatite; likely quartz–feldspar–mica aggregate

Serpentinite with carbonate veins and weathering rind

Serpentinite; chiefly serpentine-group minerals (antigorite, lizardite, chrysotile), with calcite/magnesite and accessory magnetite

Weathered gray-green basaltic rock

Basalt, likely altered to low-grade greenschist/amphibolite facies

Iron-rich concretion or slag-like rock

Goethite–hematite limonite concretion, possibly iron slag

Greenstone / altered basalt (probable)

Chlorite–epidote–actinolite aggregate; commonly metabasalt (greenstone)

Iron-rich breccia or weathered ironstone

Goethite–hematite-bearing ferruginous rock, possibly limonite

Serpentine-rich metamorphic rock

Serpentinite, likely with quartz or calcite veining and minor magnetite

Eclogite

Eclogite (Omphacite-Garnet rock)

Amphibolite

Amphibolite (rich in amphibole and plagioclase feldspar)

Quartz-bearing rock, possibly weathered granite or pegmatite

Quartz–feldspar–mica aggregate; exact classification is uncertain from the image

Quartz-rich pegmatite (weathered feldspar–quartz rock)

Granitic pegmatite; primarily quartz (SiO₂), feldspar, and minor biotite/iron-oxide minerals

Quartzite

Quartzite (SiO2)

Granite

Phaneritic Igneous Rock (composed primarily of Quartz, Alkali Feldspar, and Plagioclase)

Uncertain polymict breccia or altered volcanic rock

Likely hydrothermally altered volcanic breccia; exact mineral identification requires testing

Granite

Granite (Felsic intrusive igneous rock)

Mica Schist

Mica Schist (primarily Muscovite or Biotite)

Gneiss

High-grade Metamorphic Gneiss

Quartz-bearing dark mineral specimen

Quartz (SiO₂) on a dark host rock, possibly basalt or sulfide-rich ore

Serpentine-rich metamorphic rock

Serpentinite; chiefly antigorite/lizardite Mg₃Si₂O₅(OH)₄, possibly with talc, chlorite, magnetite, or carbonate

Weathered, iron-stained feldspathic rock (probable granite or granitic pegmatite)

Quartz–feldspar granitoid; visible blue grains may be altered feldspar or accessory minerals

Polished green jasper cabochon (likely serpentine or nephrite imitation)

Jasper: microcrystalline quartz (SiO₂); green coloration may reflect chlorite, epidote, or iron minerals

Dalmatian jasper (likely orbicular microgranite)

Quartz–feldspar–biotite/pyroxene microgranite; commonly marketed as Dalmatian jasper