Sedimentary (Secondary Classification For A Weathered Mineral Specimen)

Granite

Granite (Phaneritic Acidic Igneous Rock)

Botryoidal Chalcedony

Chalcedony (SiO2)

Yellow Agate

Agate (Varietal form of Chalcedony/Quartz, SiO2)

Granite Pebble

Granite (Phaneritic intrusive igneous rock comprising Quartz, Feldspar, and Mica)

Gold Nugget

Native Gold (Au)

Turquoise (beads)

Turquoise; CuAl6(PO4)4(OH)8·4H2O

Vesicular Basalt (Scoria)

Basalt (Extrusive Igneous Rock)

Sandstone (with Iron Staining)

Clastic sedimentary rock (primarily SiO2 with Fe2O3 oxides)

Basalt Pebble

Extrusive Mafic Volcanic Rock

Fossil Rugose Coral (Horn Coral)

Order Rugosa (likely Grewingkia or Heliophyllum species); Calcium Carbonate (CaCO3)

Prehnite

Prehnite, Ca2Al(AlSi3O10)(OH)2

Carnelian Agate

Silicon Dioxide (SiO2)

Sandstone

Arenite (composed primarily of SiO2)

Sandstone (with potential trace fossils)

Clastic sedimentary rock (primarily SiO2)

Purple Dyed Agate Geode (Banded Chalcedony)

Silicon Dioxide (SiO2) - variety: Agate

Quartz Pebble

Silicon Dioxide (SiO2)

Quartz (likely a macrocrystalline variety like milky quartz or smoky quartz, given the appearance in the image)

Quartz (SiO₂ - Silicon Dioxide)

Prehnite

Ca2Al(AlSi3O10)(OH)2 (Calcium Aluminum Silicate hydroxide)

Azurite and Malachite on Matrix

Azurite: Cu3(CO3)2(OH)2; Malachite: Cu2CO3(OH)2

Granite Cobble

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

Milky Quartz with Iron Staining

Quartz (Silicon Dioxide, SiO2)

Fossilized Sea Urchin (Echinoid)

Echinoidea (Class); commonly Clypeasteroida for sand dollar types

Diamond (Cut Specimen)

Carbon (C)

Basalt (River Stone)

Basalt (Mafic Extrusive Igneous Rock)

Quartz

Silicon dioxide (SiO₂)

Quartzite (River Pebble)

Meta-quartzite (composed primarily of SiO2)

Sandstone (with Lichen)

Arenite (composed primarily of SiO2)

Ironstone Concretion / Limonite-stained Siltstone

Ironstone (primarily Limonite FeO(OH)·nH2O and Siltstone)

Banded Agate (specifically Carnelian Agate color)

Silicon Dioxide (SiO2) - variety of Chalcedony

Limonite (Iron Ore)

Limonite (FeO(OH)·nH2O)

Concretion or Geode (unbroken)

Varied (depending on mineral composition and cementing agent). For quartz-lined geodes, the scientific name of the dominant mineral would be Quartz (SiO2). For calcite-lined geodes, Calcite (CaCO3). Concretions are often composed of cryptocrystalline quartz (chert), calcite, or iron oxides.

Silver (Jewelry Specimen)

Native Silver (Ag)

Red Carnelian

Carnelian (Silicon Dioxide - SiO2)

River Rock (Basalt)

Aphanitic Basaltic Rock

Basalt (Weathered/River worn)

Mafic Volcanic Rock (Primarily Plagioclase Feldspar and Pyroxene)

Gold Grain

Native Gold (Au)

Quartz

Silicon Dioxide (SiO2)

Quartz Pebble

Silicon Dioxide (SiO2)

Yellow Agate

Silicon Dioxide (SiO2) - variety of Chalcedony

Granite Cobble

Felsic Intrusive Igneous Rock

Amethyst (Quartz)

Silicon Dioxide with Iron impurities (SiO2)

Azurite

Azurite (Cu3(CO3)2(OH)2)