Mineral

Blue apatite crystal cluster

Apatite-group mineral, most likely fluorapatite — Ca₅(PO₄)₃F

Likely serpentinite (green serpentine rock)

Serpentinite, composed chiefly of serpentine-group minerals (antigorite, lizardite, and/or chrysotile)

Metamorphic rock with large feldspar crystals (likely porphyroblastic gneiss)

Feldspar-porphyroblastic gneiss; likely quartz and feldspar with mica/amphibole, identification from image only

Banded Gneiss

Gneiss (Foliated Metamorphic Rock)

Granite

Granite (composed mainly of Quartz, Potassium Feldspar, Plagioclase, and Biotite/Mica)

Gneiss (specifically Granite Gneiss)

Gneiss (High-grade Regional Metamorphic Rock)

Tumbled agate/chalcedony

Microcrystalline quartz (SiO₂), likely mossy or dendritic agate with iron-oxide inclusions

Fluorite

Calcium Fluoride (CaF2)

Talc Schist / Soapstone

Talc (Mg3Si4O10(OH)2)

Quartz Druze on Matrix

Silicon Dioxide (SiO2)

Likely iron-rich granite or granitic gneiss

Quartz–feldspar rock with iron-oxide staining; exact identification is uncertain from the image

Fine-grained brown-gray rock, possibly andesite

Likely andesite or another fine-grained volcanic rock; exact identification is uncertain from the photo

Devil's Toenail (Fossil Oyster)

Gryphaea arcuata (Calcium Carbonate, CaCO3)

Jasper

SiO2 (Cryptocrystalline quartz)

Blue Apatite

Fluorapatite (Ca5(PO4)3F)

Limonite (Yellow Ochre)

Hydrated Iron Oxide (FeO(OH)·nH2O)

Limonite and Goethite on Gossan

FeO(OH)·nH2O

Limonite (Iron Ore)

Limonite (FeO(OH)·nH2O)

Malachite

Copper(II) carbonate hydroxide [Cu2CO3(OH)2]

Ironstone (Limonite/Hematite)

Ferruginous sedimentary rock (Fe2O3·nH2O / Fe2O3)

Pegmatite

Pegmatite (felsic intrusive igneous rock)

Limonite with Pyrite

Hydrated Iron Oxide Hydroxide, FeO(OH)·nH2O

Mixed Mineral Collection

Multiple Mineral Species (Silicates and Oxides)

Small rough mineral fragment, possibly quartz or feldspar

Unidentified silicate mineral; image is insufficient for a reliable species identification

Small tan mineral or rock fragment (unidentified)

Indeterminate from the image; no diagnostic features are visible

Small amber-colored mineral fragment (identity uncertain)

Undetermined; appearance alone is insufficient for a reliable mineral identification

Small cylindrical mineral/stone fragment

Undetermined; the image is insufficient for reliable mineral identification

Limonite with Quartz

Hydrated Iron Oxide Hydroxide, FeO(OH)·nH₂O with SiO₂

Weathered rock with a tan mineral vein or inclusion

Indeterminate from the photograph; possibly a quartz- or feldspar-rich vein in dark metamorphic host rock

Vesicular basalt

Basalt, commonly plagioclase feldspar + pyroxene ± olivine

Tiger's Eye

Quartz pseudomorph after crocidolite (SiO2)

Greenstone / Epidosite

Epidosite (primary minerals: Epidote and Quartz)

Green Jasper

Silicon Dioxide (SiO2) with mineral inclusions

Azurite Malachite (Mixed)

Azurite-Malachite; Azurite: Cu3(CO3)2(OH)2 / Malachite: Cu2CO3(OH)2

Epidote

Epidote, Ca2(Al,Fe)3(SiO4)3(OH)

Granite (likely)

Granite, a quartz–feldspar–mica intrusive igneous rock

Granite

Granite (felsic intrusive igneous rock)

Granite

Granite, a coarse-grained felsic intrusive igneous rock composed mainly of quartz, feldspar, and mica

Quartz in Greenstone

Metamorphic rock with quartz vein (SiO2 / mixed silicates)

Likely green-schist specimen

Greenschist, a chlorite–epidote–actinolite-bearing metamorphic rock

Gneiss

Gneiss (a rock type, not a specific mineral with a formula)

Quartz (Druzy)

Silicon Dioxide (SiO2)