The Purple Specimen Is A Mineral (Amethyst); The White Specimen Is A Sedimentary Rock (Limestone Or Marble).

Banded Agate (Agatized Geode Slice)

Silicon Dioxide (SiO₂)

Copper Ore with Malachite and Chrysocolla

Cu2CO3(OH)2 (Malachite) with Cu2-xAlx(H2-xSi2O5)(OH)4·nH2O (Chrysocolla)

Druzy Quartz (on Quartzite or Chert)

Silicon Dioxide (SiO2)

Clear Quartz

SiO2 (Silicon Dioxide)

Chert (specifically Flint or Common Chert)

Microcrystalline Quartz (SiO2)

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

Raw Corundum (Sapphire/Ruby variant)

Aluminum oxide (Al2O3)

Milky or Iron-Stained Quartz

Quartz (Silicon Dioxide, SiO2)

Ferruginous Sandstone (River Pebble)

Clastic Sedimentary Rock (primarily SiO2 with Fe2O3 cement)

Quartzite

Quartzite (SiO2)

Quartz Pebble

Silicon Dioxide (SiO2)

Granite

Phaneritic Plutonic Felsic Rock

Amethyst (Quartz Cluster)

Silicon Dioxide (SiO2) with iron impurities

Okenite (in Zeolite matrix)

Okenite (CaSi2O5 · 2H2O)

Carnelian Agate

Silicon Dioxide (SiO2) with iron oxide impurities

Quartzite

Quartzite (primarily SiO2)

Limestone

Calcium Carbonate (CaCO3)

Granite Pebble

Granite (Felsic Plutonic Rock)

Ironstone Concretion (Moqui Marble)

Iron Oxide Concretion (Fe2O3 / FeO(OH) mixed with SiO2)

Petrified Wood

Silicified Wood (primarily SiO2 - Silicon Dioxide)

Milky Quartz

Silicon Dioxide (SiO2)

Rhodochrosite

Manganese carbonate (MnCO3)

Dyed Pink Agate

Silicon Dioxide (SiO2) - variety Chalcedony

Granite Pebble

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

Milky Quartz

Silicon Dioxide (SiO2)

Chert (Flint Nobule)

Silicon Dioxide (SiO2)

Pink Quartzite

Quartzite (primarily SiO2 with trace impurities of iron oxides)

Sandstone Concretion

Moqui Marble / Iron-oxide Concretion (SiO2 with Hematite/Goethite)

Garnet in Schist (Garnetiferous Micaceous Schist)

Almandine Garnet, Fe3Al2(SiO4)3

Yellow Jasper

Silicon Dioxide with iron inclusions (SiO2)

Black Limestone with Calcite Veining

Bituminous Limestone (CaCO3 with Organic Carbon inclusions)

Chert (Jasper variety)

Silicon Dioxide (SiO2)

Limestone

Sedimentary Calcium Carbonate (CaCO3)

Peacock Ore (Bornite or Iridescent Chalcopyrite)

Bornite (Cu5FeS4) or Chalcopyrite (CuFeS2) with oxidation

Milky Quartz Pebble

Quartz (Silicon Dioxide, SiO2)

Chert (Green variety)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Bornite (Peacock Ore)

Bornite (Cu5FeS4)

Quartz-bearing Ore (likely Gold-bearing Quartz)

Quartz (SiO2) with potential sulfide mineralization (Pyrite/Arsenopyrite)

Pink Quartzite

Quartzite (SiO2)

Limestone

Calcium Carbonate (CaCO3)

Granite Cobble

Felsic Intrusive Igneous Rock (Granite)

Pyrite with Calcite

Iron Disulfide (FeS2) with Calcium Carbonate (CaCO3)