Igneous Or Sedimentary (Water Worn)

Clear Quartz

Quartz (Silicon Dioxide, SiO2)

Quartz pebble / River stone

SiO2 (Silicon Dioxide)

Polygenetic Conglomerate (Puddingstone)

Conglomerate (SiO2 matrix with mixed clasts)

Basalt with Epidote (Porphyry)

Basalt (with inclusions of Epidote/Feldspar)

Dendritic Opal (Common Opal)

Amorphous Hydrated Silica (SiO2·nH2O) with Manganese or Iron Oxide inclusions

Satin Spar (Selenite variant)

Gypsum (Calcium Sulfate Dihydrate, CaSO4·2H2O)

Hematite

Iron(III) oxide (Fe2O3)

Greywacke (River Pebble)

Dirty Sandstone (SiO2 with lithic fragments)

Native Gold Nuggets

Native Gold (Au)

Sandstone (Quartzose Sandstone)

Arenite

Jasper (Green Jasper / Bloodstone variant base)

Silicon Dioxide (SiO2) with impurities of chlorite and iron oxides

Spondylus Oyster Calcification / Fossilized Oyster

Spondylus (Thorny Oyster) / Calcium Carbonate (CaCO3)

Chert (with Limonite staining)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Chert (Jasper variety)

Silicon Dioxide (SiO2)

Granite

Phaneritic Felsic Igneous Rock (primarily Quartz, Feldspar, and Mica)

Satin Spar (Selenite)

Calcium sulfate dihydrate (CaSO4·2H2O)

Red Porphyry

Porphyritic Andesite or Rhyolite

Jasper or Chert

Silicon Dioxide (SiO2)

Megalodon Tooth

Otodus megalodon

Fossiliferous Limestone (Gritstone/Marl)

CaCO3 (Calcium Carbonate) with Fossil Inclusions

Oolite or Oolitic Limestone

Oolitic Limestone (Principal mineral: Calcite, CaCO3)

Basalt (River Pebble)

Basalt (Aphanitic Mafic Volcanic Rock)

Chert (specifically Blue or Grey Chert/Flint)

Microcrystalline or cryptocrystalline Quartz (SiO2)

Chert (varieties include Flint and Jasper)

Silicon Dioxide (SiO2)

Sodalite Syenite

Sodalite-bearing Syenite (Na8(Al6Si6O24)Cl2)

Quartzite (Yellow/Orange variety)

Quartzite (primarily SiO2)

Banded Calcite (Mexican Onyx)

Calcium Carbonate (CaCO3)

Chert (Iron-stained)

Microcrystalline Quartz (SiO2)

Milky Quartz Pebble

Quartz (Silicon Dioxide - SiO2)

Black Tourmaline (Schorl)

Schorl (Na(Fe²⁺)₃Al₆(BO₃)₃Si₆O₁₈(OH)₄)

Yellow Chalcedony (Carnelian/Yellow Agate)

Silicon Dioxide (SiO2) - Microcrystalline Quartz

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

Sandstone

Arenite (SiO2 primarily)

Greywacke (River Pebble with Quartz Veins)

Greywacke (Indurated Sandstone); Veins: SiO2 (Quartz)

Almandine Garnet

Almandine (Fe3Al2(SiO4)3)

Halite

Halite (Sodium Chloride, NaCl)

Banded Gneiss

Gneiss (Metamorphic high-grade rock)

Chert (Jasper/Quartzite river stone)

Microcrystalline Silicon Dioxide (SiO2)

Pumice

Vesicular Rhyolite or Dacite Pumice (Amorphous volcanic glass)

Basalt (River-worn Pebble)

Aphanitic Mafic Igneous Rock

Red Garnet

Pyrope-Almandine series (Mg3Al2(SiO4)3 to Fe3Al2(SiO4)3)

Veined Pebble (likely a Quartz-Veined Pebble)

Pebble with Mineral Vein (e.g., Quartz Vein in a Chert/Mudstone Pebble)