Sedimentary Or Metamorphic (Base Substrate)

Carved red coral bead (likely coral or coral-colored resin)

Corallium spp. (precious coral; calcium carbonate, CaCO₃)

Sandstone

Arenite (predominantly SiO2)

Biotite-rich schist (mica schist)

Mica schist, dominated by biotite mica (K(Mg,Fe)₃AlSi₃O₁₀(F,OH)₂), with probable quartz and feldspar

Jasper Conglomerate (Puddingstone)

Siliceous Conglomerate (Quartz and Jasper clasts in a fine-grained matrix)

Gneiss (Granitic Gneiss)

Gneiss

Diamond Drill Core (Greenschist and Quartzite)

Chlorite Schist / Meta-quartzite (Metamorphic Rock Core Sample)

Polished mica-rich metamorphic sphere

Likely mica schist or garnet-mica schist; exact identification is uncertain from the photograph

Biotite-rich schist (mica schist)

Mica schist, chiefly biotite (K(Mg,Fe)₃AlSi₃O₁₀(OH,F)₂), with possible quartz and feldspar

Gneiss

Gneiss

Muscovite

Muscovite mica, KAl2(AlSi3O10)(OH)2

Biotite-rich gneiss or schist

Mica gneiss/schist; primarily quartz, feldspar, biotite, and possibly amphibole

Epidote

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

Quartzite Pebble

Metamorphic Quartzite (SiO2)

Mixed river gravel (alluvial conglomeratic sediment)

Polymictic alluvium; composition includes quartz, feldspar, chert, granite, basalt, and metamorphic rock fragments

Chert Arrowhead

Cryptocrystalline Quartz (SiO2)

Quartzite Cobble

Quartzite (SiO2 based)

Epidote

{Ca2}{Al2Fe3+}(Si2O7)(SiO4)O(OH)

Metallic sulfide mineral fragment, likely galena

Galena (lead sulfide, PbS), tentative identification

Quartz Pebble with Host Rock / Schist Matrix

Silicon Dioxide (SiO2) with Metamorphic Host Rock

Epidote

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

Mica-rich schist, likely lepidolite or muscovite schist

Mica schist; predominantly muscovite KAl₂(AlSi₃O₁₀)(OH)₂, possibly lithium-rich lepidolite

Goethite pseudomorph after Pyrite

Goethite (FeO(OH)) pseudomorph after Pyrite (FeS2)

Fuchsite (Chrome Mica)

K(Al,Cr)2(AlSi3O10)(OH)2

Gneiss (specifically a Banded Gneiss pebble)

Gneiss (High-grade Regional Metamorphic Rock)

Fossil shark tooth

Likely fossilized shark tooth, possibly *Carcharocles* or *Otodus* species

Unidentified Rock Fragment

Unknown

Basalt (Weathered River Pebble)

Extrusive Igneous Rock

Serpentinite

Serpentinite (Mg, Fe, Ni, Al, Zn, Mn)2-3(Si, Al, Fe)2O5(OH)4

Sandstone (Ferruginous)

Arenite with Iron oxide staining (SiO2 with Fe2O3)

Yellow Beryl

Beryllium Aluminum Silicate, Be3Al2(SiO3)6

Quartzite Cobble

Quartzite (SiO2 based metamorphic rock)

Anthracite Coal

Anthracite (Carbon-based metamorphic rock)

Fossil shark tooth

Likely fossilized shark tooth, possibly Carcharhinus or Otodus species

Mica Schist

Schist (muscovite/biotite rich regional metamorphic rock)

Graphite-rich schist (likely graphite ore)

Graphite-bearing schist; predominantly graphitic carbon (C) with mica, quartz, and possible feldspar

Mica-rich schist (likely biotite schist)

Biotite schist; quartz- and feldspar-bearing, with abundant mica

Mica Schist with Biotite or Muscovite

Metamorphic rock rich in sheet silicates

Muscovite

Muscovite, KAl2(AlSi3O10)(OH)2

Muscovite

KAl2(AlSi3O10)(OH)2

Pearl

Nacre (aragonite, CaCO₃, in an organic conchiolin matrix)

Pyrite-bearing rock, possibly pyrite schist or sulfide ore

Pyrite (iron disulfide, FeS₂), likely intergrown with dark metamorphic host minerals

Epidote

Calcium aluminum iron silicate (Ca2(Al, Fe)3(SiO4)3(OH))