Mineral (Pseudomorph)

Pearl (Biogenic Mineral)

Calcium Carbonate (primarily Aragonite) with Conchiolin; CaCO3

Hematite Mineral Ore

Iron(III) oxide (Fe2O3)

Pearl (as a Biogenic Mineral)

Calcium Carbonate (mostly Aragonite) with Conchiolin; CaCO3

Pegmatite

Igneous Pegmatite (Quartz-Feldspar-Biotite)

Septarian Nodule

Septarian Concretion (Calcite, Aragonite, and Limestone)

Fossilized Shark Tooth (Megalodon or Carcharocles fragment)

Elasmobranchii (Fossilized tooth root / crown section)

Granodiorite

Granodiorite (intermediate plutonic rock)

Rounded quartz-rich cobble, likely granite-derived stone

Granite or granitic gneiss, composed mainly of quartz, feldspar, and minor mica

Milky quartz (quartz-rich rock)

Quartz, silicon dioxide (SiO₂); likely massive quartz with minor iron-stained impurities

Milky quartz

Quartz (silicon dioxide, SiO₂)

Green Jasper Pebble

Microcrystalline Quartz (Chalcedony), SiO2

Bauxite

Bauxite (Al(OH)3, AlO(OH))

White Quartz with Black Tourmaline

Silicon Dioxide (SiO2) with Schorl (NaFe2+3Al6(Si6O18)(BO3)3(OH)3OH)

Quartz (with probable host rock)

Silicon Dioxide (SiO2)

Bauxite

Bauxite (Al2O3·nH2O)

Olivine in Basalt (Peridotite Xenolith)

Forsterite-rich Olivine (Mg2SiO4) in Aphanitic Basalt

Banded Chert

Microcrystalline Quartz (SiO2)

Bauxite

Bauxite (Al2O3·nH2O)

Limonite-stained Quartz

Silicon Dioxide (SiO2) with Iron Oxide/Hydroxide (FeO(OH)·nH2O) staining

Chert (specifically Flint or Jasper variant)

Microcrystalline Quartz (SiO2)

Lapis Lazuli

Lapis Lazuli (A metamorphic rock primarily composed of Lazurite: (Na,Ca)8(AlSiO4)6(S,Cl,SO4,OH)2)

Limonite

Limonite (FeOO·nH2O)

Chrysocolla on Matrix

Hydrated copper phyllosilicate (Cu,Al)2H2Si2O5(OH)4·nH2O

Chalcopyrite (Peacock Ore)

Copper Iron Sulfide (CuFeS2)

Aquamarine

Beryl (Be3Al2Si6O18 with trace Fe2+)

Epidote

Epidote (formula: Ca2(Al2,Fe3+)(SiO4)(Si2O7)O(OH))

Rounded pink granite pebble

Granite, chiefly quartz, alkali feldspar, plagioclase, and minor biotite/hornblende

Greenschist (or Serpentinite) with Quartz-Feldspar Vein

Metabasalt / Greenschist Facies Rock

Uncertain small pale mineral fragment

Indeterminate; possibly calcite or a light-colored feldspar fragment

Green copper-mineral specimen, likely chrysocolla or copper-bearing serpentine

Tentatively chrysocolla (hydrated copper phyllosilicate, approximately (Cu,Al)2H2Si2O5(OH)4·nH2O); exact identification requires testing

Blue quartz-like mineral specimen

Likely quartz (SiO₂), possibly dyed or coated; exact identification requires testing

Small polished pink-and-white mineral pebble

Likely rose quartz or pale pink quartz; exact identification is uncertain from the image

Raw smoky quartz with dark mineral inclusions

Quartz (SiO₂), likely smoky quartz; dark inclusions may be chlorite, tourmaline, or iron/manganese oxides

Dyed mineral cluster, likely calcite or aragonite

Calcite (CaCO₃) or aragonite (CaCO₃), artificially color-enhanced

Blue mineral specimen, likely bornite (“peacock ore”)

Bornite, Cu5FeS4, possibly iridescent chalcopyrite (CuFeS2)

Small brown-gray mineral fragment

Indeterminate; possibly weathered quartz-, feldspar-, or iron-oxide-bearing rock

Pale green rough mineral specimen, likely serpentine or calcite

Probable serpentine-group mineral, Mg₃Si₂O₅(OH)₄; possibly pale-green calcite, CaCO₃

Polished black mineral or volcanic glass fragment

Indeterminate; possibly obsidian or black tourmaline

Small dark mineral/rock fragment

Indeterminate; possibly magnetite-bearing basalt or iron-rich slag

Pale green tumbled mineral fragment, likely serpentine or green calcite

Probable serpentine-group mineral (Mg3Si2O5(OH)4) or, less likely, calcite (CaCO3); identification is uncertain from the photograph

Blue-green copper mineral specimen, likely chrysocolla or turquoise

Probable chrysocolla, hydrated copper phyllosilicate (Cu₂H₂Si₂O₅(OH)₄·nH₂O); turquoise, CuAl₆(PO₄)₄(OH)₈·4H₂O, is an alternative

Sandstone (Iron-stained)

Clastic sedimentary rock (primarily SiO2 with Fe2O3 staining)