Metamorphic Or Sedimentary Depending On Local Grade

Conglomeratic breccia (polymict volcanic breccia)

Polymict volcaniclastic breccia; clasts likely basaltic/andesitic rock in a dark matrix

Apatite

Calcium phosphate fluoride/chloride, Ca5(PO4)3(F,Cl,OH)

Fossilized bivalve or ammonite fragment

Calcareous fossil; likely a mollusk shell preserved as calcite (taxonomic identification uncertain)

Feldspar-rich Granite (or Gneiss) Pebble

Granite (primarily Orthoclase Feldspar and Quartz)

Gneiss

High-grade Metamorphic Gneiss

Gneissic granite / granitic gneiss

Quartz–feldspar–mica gneiss; composition commonly quartz (SiO₂), feldspars, and biotite/muscovite

Ruby in Zoisite

Anyolite (combination of Ca2Al3(SiO4)3(OH) and Al2O3:Cr)

Clear Quartz (Faceted)

SiO2 - Silicon Dioxide

Quartz-bearing weathered rock

Massive to drusy quartz (SiO₂), possibly in a feldspathic or carbonate host

Blue-gray chalcedony (likely common quartz/chert)

Microcrystalline quartz, SiO₂; possibly weathered chert or chalcedony

Banded gneiss

Gneiss, composed mainly of quartz, feldspar, and mica

Libyan Desert Glass

Libyan Desert Glass (Impactite / High-silica Lechatelierite)

Slate

Metamorphic Pelitic Rock

Gneiss

Metamorphic Gneiss

Weathered dark metamorphic rock, likely slate or phyllite

Fine-grained foliated rock, probably slate/phyllite; exact identification requires testing

Jadeite Jade

NaAlSi2O6 (Sodium Aluminum Silicate)

Ruby in Zoisite (Anyolite)

Anyolite (Combination of Corundum and Zoisite)

Gravel and River Pebbles

Unconsolidated rock fragments / Detrital sediment

Quartzite

Quartzite (SiO2)

Mica Schist

Schist (biotite/muscovite schist)

Greenstone (likely altered mafic rock)

Chlorite- and amphibole-bearing metabasalt; exact identification requires testing

Dark coarse-grained metamorphic rock, likely amphibolite or hornblende schist

Amphibolite, dominated by hornblende amphibole and plagioclase feldspar; exact identification requires testing

Rough Blue Sapphire

Corundum (Al2O3)

Hypersthene

Hypersthene (Enstatite variety), (Mg,Fe)SiO3

Rhodochrosite

Manganese Carbonate (MnCO3)

Gneiss

Gneiss (High-grade metamorphic rock)

Schist

Mica schist, typically muscovite–biotite quartz schist

Gneiss

Gneiss (Metamorphic high-grade)

Chert in Limestone (or Flint Nodule)

Silicon Dioxide (SiO2) within Calcium Carbonate (CaCO3)

Weathered porphyritic volcanic rock, likely rhyolite or andesite

Porphyritic rhyolite–andesite; mainly quartz/feldspar phenocrysts in a fine iron-stained groundmass

Banded gneiss (likely granitic gneiss)

Foliated gneiss composed mainly of quartz, feldspar, and dark biotite/amphibole

Slate

Foliated Metamorphic Rock (composed of quartz, illite, chlorite)

Turquoise

CuAl6(PO4)4(OH)8·4H2O

White Buffalo Turquoise (or Howlite/Magnesite)

Calcite/Dolomite or Magnesite with Chert/Quartz inclusions

Mystic Topaz (Treated Quartz or Topaz)

Aluminum silicate fluoride hydroxide [Al2SiO4(F,OH)2] with thin-film metallic coating

Polished brecciated turquoise-like copper mineral

Likely chrysocolla–malachite–limonite assemblage; possibly turquoise-bearing copper ore

Gneiss

High-grade Metamorphic Gneiss

Greenstone / altered mafic rock

Likely chlorite–actinolite metabasalt (greenschist); exact identification requires testing

Coquina / Shelly Sandstone

Calcareous Sandstone / Coquina

Porous fossil fragment (possibly fossilized coral or shell)

Unidentified fossil carbonate; likely calcite/aragonite

Anthracite

Anthracite coal

Morganite and Aquamarine (Beryl) Bracelet

Beryllium aluminum silicate, Be3Al2(SiO3)6