Mineral (Tectosilicate)

Purple amethyst crystal specimen

Amethyst, purple variety of quartz (SiO₂)

Sandstone with Ironstone Concretion

Arenite with Ferruginous Cement

Granite pebble

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

Small brown mineral or rock fragment (not identifiable from the image)

Undetermined; the specimen is too small and lacks visible diagnostic features for reliable identification

Small brown mineral or rock fragment

Undetermined; the image lacks enough detail for a reliable identification

Calcite (commonly referred to as Orange Calcite or Honey Calcite given its color)

Calcite

Weathered greenstone (probable)

Chlorite–actinolite–epidote metamafic rock; exact identification requires testing

Likely dyed or painted stone

Unidentified natural rock; vivid purple, orange, and pink coloration appears to be a surface coating or pigment, so the underlying rock cannot be reliably identified from the image.

Greenstone (likely chlorite-rich metamorphic rock)

Chlorite-rich greenschist; commonly composed of chlorite, actinolite, and epidote

Small dark rock fragment (unidentified)

Undetermined; composition cannot be identified reliably from this photograph

Dark, speckled coarse-grained rock; likely diorite

Diorite, an intrusive igneous rock composed mainly of plagioclase feldspar and hornblende or other dark minerals

Likely gneiss

Quartz–feldspar–mica gneiss (visual identification is uncertain)

Black Sand (Magnetite/Heavy Mineral Concentrate)

Magnetite-rich Placers (Fe3O4)

Quartz-rich hydrothermal mineral specimen, possibly vanadinite-bearing matrix

Quartz (SiO₂) with unidentified red-brown accessory minerals; exact species requires testing

Banded quartz-rich rock (possibly pegmatite)

Likely quartz–feldspar pegmatite; identification is tentative from the photo

Limonite / Goethite Ironstone

FeO(OH)·nH2O (Hydrous iron oxide)

Quartz Vein in Hematitic Siltstone

Hydrothermal Quartz (SiO2) in Ferriferous Matrix

Tumbled serpentine (likely green serpentinite)

Serpentine-group minerals, commonly antigorite, lizardite, or chrysotile; serpentinite is the rock

Rounded granite cobble

Granite, a coarse-grained felsic intrusive igneous rock

Mixed Mineral Collection

Various Silicates and Oxides

Pyrite

Iron Disulfide (FeS2)

Gypsum (Selenite sand)

Calcium sulfate dihydrate (CaSO4·2H2O)

Fluorite on Host Rock

Calcium Fluoride (CaF2)

Pyrite

Iron Pyrite (FeS2)

Pyrite

Iron Sulfide (FeS2)

Eudialyte

Na15Ca6Fe3Zr3Si(Si25O73)(O,OH,H2O)3(Cl,OH)2

Rhodochrosite with Quartz

Manganese Carbonate (MnCO3) with Silicon Dioxide (SiO2)

Turquoise

Hydrated phosphate of copper and aluminium (CuAl6(PO4)4(OH)8·4H2O)

Polished picture jasper (likely)

Silica-rich microcrystalline quartz, SiO₂, with iron-oxide and other mineral inclusions

Weathered garnet-bearing gneiss (likely)

Garnet-bearing gneiss; exact mineral identification is uncertain from the photograph

Banded Sandstone (Water-worn Pebble)

Arenite with mineral banding

Quartz-rich pegmatite fragment

Granite/pegmatite; chiefly quartz (SiO₂) and feldspar, with possible biotite or tourmaline

Pegmatite

Igneous Pegmatite

Fluorite Tower

Fluorite (Calcium Fluoride - CaF2)

Blue-green mineral fragment, possibly turquoise

Unidentified copper-bearing mineral; turquoise is CuAl₆(PO₄)₄(OH)₈·4H₂O

Iron-stained quartz vein in altered host rock

Quartz (SiO₂) with iron oxides/hydroxides, likely hematite and goethite; host rock uncertain from the image

Pink potassium feldspar (orthoclase/microcline)

KAlSi₃O₈; likely massive potassium feldspar, possibly with quartz

Fossil brachiopod shell

Brachiopoda; exact genus and species cannot be determined from the image

Feldspar

Aluminosilicate (KAlSi3O8 - NaAlSi3O8 - CaAl2Si2O8)

Likely garnet (rough, dark-red variety)

Garnet group; possibly almandine, Fe₃Al₂(SiO₄)₃

Greenschist

Chlorite Schist (Greenschist Facies)

Limonite

FeO(OH)•nH2O