Mineral (Silicate Replaced Organic Material)

Fossil coral pebble and banded stone

Likely fossilized tabulate or rugose coral (left); right specimen may be silicified coral or weathered limestone

Unakite (bottom) and Sodalite (top)

Epidotized Granite (Unakite) and Sodium Aluminum Silicate Chloride (Sodalite)

Polished stone sphere, possibly agate or jasper

Likely microcrystalline quartz (SiO₂); exact variety cannot be confirmed from the image

Fossilized Coral (Petoskey Stone or Tabulate Coral)

Scleractinia or Tabulata (CaCO3 - Calcium Carbonate)

Petrified Palmwood

Palmoxylon (fossilized monocot xylem)

Chert (Jasper-like Silicate)

Microcrystalline quartz (SiO2)

Mother of Pearl (Nacre)

Aragonite (CaCO3) with Organic Matrix

Pink opal

Common opal, hydrated amorphous silica (SiO₂·nH₂O), commonly colored by trace organic or iron compounds

Fossil gastropod (snail)

Fossilized gastropod shell, likely a marine mollusk; exact genus cannot be determined from the image

Unidentified small mineral fragments

Likely quartz- or feldspar-rich material; species cannot be determined reliably from the image

Fossil bivalve shell

Likely fossilized cockle or other marine bivalve; exact genus requires locality and internal features

Petrified Wood

Silicified Wood (SiO2)

Petrified Wood

Silicified Wood (SiO2)

Fossilized Shark Tooth (Otodus)

Otodus sp. (calcium phosphate/hydroxylellite)

Weathered mineralized rock fragment

Indeterminate; likely quartz–feldspar-rich lithic material with iron-oxide staining

Slag (Industrial Byproduct)

Artificial silicate/iron byproduct

Sandstone (with Moss)

Quartz Arenite / Sandstone

Fossilized tooth or jaw fragment (likely fish or reptile)

Indeterminate vertebrate bone/tooth; mineralized hydroxyapatite, commonly Ca₅(PO₄)₃(OH)

Graphite-rich schist (likely graphite ore)

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

Black Kyanite

Aluminum Silicate (Al2SiO5)

Polished orbicular jasper (likely ocean jasper)

Microcrystalline quartz/chalcedony, SiO₂, with variable iron-oxide and other mineral inclusions

Polished brecciated jasper

Microcrystalline quartz (SiO₂) with hematite/goethite and pale chalcedony or feldspar inclusions

Flint (chert) nodule

Microcrystalline quartz (SiO₂), occurring as a flint/chert nodule in limestone

Chert (Flint)

Microcrystalline Quartz (SiO2)

Fossilized Brain Coral

Diploria labyrinthiformis (Fossilized)

Polished brecciated jasper (likely yellow-and-white jasper)

Jasper, an opaque microcrystalline variety of quartz (SiO₂); exact variety cannot be confirmed from the image

Sedimentary Rock (Limestone or Siltstone pebble)

Sedimentary rock fragment

Polished orbicular jasper (likely ocean or leopard jasper)

Silica-rich microcrystalline quartz/chalcedony with iron-oxide and other mineral inclusions; SiO₂-dominant

Tumbled jasper/chalcedony pebbles

Microcrystalline quartz (SiO₂), likely jasper and brown chalcedony

Fossil Coral (Honeycomb Coral)

Favosites (extinct genus of Tabulate coral)

Quartz-veined Limestone

Sedimentary limestone with quartz/calcite veinlets

Fossilized Shark Tooth

Elasmobranchii fossil (likely Odontaspididae family)

Cobalt Blue Glass / Cullet Glass

Silicon dioxide (Amorphous man-made glass)

Jasper

Microcrystalline quartz (SiO2)

Pyrite (Fool's Gold) Cube

Iron Sulfide (FeS2)

Fossilized coral with attached shell

Likely fossil coral (Scleractinia or Tabulata), with a bivalve or gastropod shell; exact identification requires microscopy

Iron Slag

Ferrous Slag (Silicate/Oxide mixture)

Dark gray flint or chert fragment

Microcrystalline quartz (SiO₂), commonly with minor chalcedony and impurities

Possible flint or black chert

Microcrystalline quartz (SiO₂), likely chert/flint

River Siltstone / Mudstone Pebble

Siltstone (composed of mixed silicate and carbonate minerals)

Fossilized Coral in Chert

Anthozoa (Class) fossil in Cryptocrystalline Quartz (SiO2)

Small rounded stone or mineral fragment

Indeterminate; likely a common quartz- or feldspar-bearing silicate fragment