Mineral Health

Quartz Geode Fragment

Silicon Dioxide (SiO2)

Azurite and Malachite on Matrix

Cu3(CO3)2(OH)2 (Azurite) and Cu2CO3(OH)2 (Malachite)

Rainbow Fluorite

Fluorite (Calcium Fluoride, CaF2)

Gneiss (probable)

Quartz–feldspar–mica gneiss; exact mineral composition cannot be confirmed from the image

Possible mafic xenolith in granite

Dark mafic inclusion, likely amphibolite or gabbro, enclosed in coarse-grained granite

Fossilized bone fragment (probable mammalian tooth or bone)

Mineralized bone, commonly hydroxyapatite [Ca5(PO4)3(OH)] replaced or impregnated by silica/calcite

Fossilized Shark Tooth

Chondrichthyes (Class)

Gneiss

Gneiss

Milky quartz

Quartz (SiO₂)

Likely biotite-rich schist

Mica schist, likely containing biotite and quartz; exact identification requires examination

Tumbled quartz or calcite specimen

Quartz (SiO₂) or calcite (CaCO₃); exact identification requires testing

Greenstone / Metabasalt

Chlorite schist or Epidiorite

Greenstone

Protolith: Basaltic rock

Greenstone

Greenschist / Meta-basalt

Agate / Chalcedony Geode

Silicon Dioxide (SiO2)

Limonite Boxwork / Iron Ore Concretion

FeO(OH)qnH2O (Hydrated iron oxide)

Botryoidal Goethite

Goethite (α-Fe3+O(OH))

Weathered serpentinized ultramafic rock

Serpentinite; chiefly serpentine-group minerals, commonly with magnetite, brucite, talc, and relict olivine/pyroxene

Quartz (Druzy or Chalcedony variant)

Silicon Dioxide (SiO2)

Potassium Feldspar (Orthoclase / Microcline)

KAlSi3O8 (Potassium Aluminum Silicate)

Tumbled green stone, likely serpentine

Serpentine-group minerals, commonly antigorite or lizardite; approximate formula Mg₃Si₂O₅(OH)₄

Weathered, quartz-rich metamorphic rock (likely schist or gneiss)

Quartz–feldspar–mica schist/gneiss, with surface lichens and iron-oxide staining

Metamorphosed mafic rock, likely amphibolite

Amphibolite, chiefly hornblende + plagioclase; possibly mafic gneiss or altered basalt

Granite

Intrusive Igneous Rock (composed of quartz, alkali feldspar, and plagioclase)

Chrysocolla-bearing rock (likely chrysocolla in a host rock)

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

Small dark mineral fragment

Undetermined; image lacks diagnostic detail for reliable identification

Limonite / Goethite (Ironstone Nodule)

Hydrated Iron(III) Oxide-Hydroxide (FeO(OH)·nH2O)

Likely quartz-rich mineral specimen

Quartz (SiO₂), possibly milky quartz or quartz-bearing rock

Tumbled greenstone (likely serpentine or nephrite-like material)

Serpentinite, chiefly serpentine-group minerals; exact identification requires testing

Green Fluorite

Calcium fluoride (CaF2)

Quartz (Druzy)

Silicon Dioxide (SiO2)

Fluorite with Quartz coating

Calcium Fluoride (CaF2) with Silicon Dioxide (SiO2)

Likely a small rough mineral specimen

Unidentifiable from the image; possibly a mica-bearing rock or green mineral

Quartz with Pyrite

Silicon Dioxide (SiO2) with Iron Sulfide (FeS2)

Diorite (likely)

Diorite, an intrusive intermediate plutonic rock

Polished granite slab

Granite, a coarse-grained quartz–feldspar plutonic rock

Fossilized tooth, likely mammoth or mastodon molar fragment

Proboscidean molar enamel and dentin; Mammuthus or Mammut sp. (tentative)

Gneiss with Quartz Veining

Gneiss (High-grade metamorphic rock)

Gneiss

Gneiss

Granite Gneiss

Gneiss (Derived from Granite protolith)

Granite Pebbles

Granite (composed primarily of Quartz SiO2, Feldspar (KAlSi3O8 – NaAlSi3O8 – CaAl2Si2O8), and Mica)

Nickel coin (U.S. currency)

Cupronickel (75% Copper, 25% Nickel alloy)