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

Sandstone (River Rock)

Arenite (composed primarily of SiO2)

Oolite or Oolitic Limestone

Oolitic Limestone (Principal mineral: Calcite, CaCO3)

Blue Apatite

Apatite (Calcium Phosphate) - Ca5(PO4)3(F,Cl,OH)

Sandstone (likely Ferruginous)

Sandstone (SiO2 with iron oxides)

Amethyst

SiO2 (Silicon Dioxide with iron impurities)

Green Quartz (Prasiolite/Adventurine)

Silicon Dioxide (SiO2) with inclusions

Fossiliferous Sandstone (with Brachiopod or Bivalve mold)

Clastic Sedimentary Rock with Macrofossil Mold

Quartz

Silicon Dioxide (SiO2)

Graphite-veined Quartzite

Meta-sedimentary Quartzite with Carbonaceous/Graphitic Inclusions (SiO2 + C)

Honey Calcite

Calcium Carbonate (CaCO3)

Amethyst

Silicon Dioxide (SiO2) with trivalent iron (Fe3+) impurities

Sandstone (Ferruginous)

Arenite (variable SiO2 with Fe2O3 staining)

Yellow Quartz (Citrine Quartz)

Silicon Dioxide (SiO2)

Chalcedony (Desert Rose or Botryoidal Chalcedony)

Silicon Dioxide (SiO2)

Sandstone (with potential Quartzite characteristics)

Clastic sedimentary rock (primarily SiO2)

Fluorite

Fluoride (Calcium Fluoride - CaF2)

Sandstone (Ferruginous)

Ferruginous Sandstone (SiO2 with Fe2O3)

Sandstone

Clastic Sedimentary Rock (primarily Quartz, SiO2)

Citrine

Yellow Quartz (SiO2)

Yellow Chert or Jasper

Microcrystalline Quartz (SiO2) with iron oxide inclusions

Chert (Arrowhead Fragment)

Microcrystalline Quartz (SiO2)

Milky Quartz (Druzy Geode fragment)

Silicon Dioxide (SiO2)

Sandstone (Ferruginous)

Arenite (Fe-rich SiO2)

Fossilized Shark Tooth (Dermal Denticle or worn tooth fragment)

Elasmobranchii (fossil remains)

Amethyst

Silicon Dioxide with iron impurities (SiO2)

Quartzite

Quartzite (SiO2)

Gneiss

Gneiss (High-grade metamorphic rock)

Sandstone (Weathered Pebble)

Arenite (primarily SiO2)

Quartz (Iron-stained or Milky Quartz)

Silicon Dioxide (SiO2)

Amethyst (Faceted)

Silicon Dioxide (SiO2) with iron impurities

Sandstone

Arenite (primarily SiO2)

Lapis Lazuli

Lapis Lazuli (a rock, not a single mineral; primary mineral is Lazurite (Na,Ca)8(AlSiO4)6(S,SO4,Cl)1-2

Amethyst

Amethyst (Silicon Dioxide - SiO2 with impurities of iron)

Sandstone

Sandstone (clastic sedimentary rock), primarily SiO2

Orange Quartz (Citrine Quartz)

Silicon Dioxide (SiO2)

Sandstone (Stream Pebble)

Arenite (primarily SiO2)

Gneiss (with Mica and Quartz)

Gneissic Metamorphic Rock

Lapis Lazuli

Lapis lazuli (a metamorphic rock primarily composed of Lazurite, (Na,Ca)8(AlSiO4)6(S,Cl,SO4,OH)2)

Green Calcite

Calcium Carbonate (CaCO3)

Chert / Flint

Chert (varieties include Flint)

Sandstone (Ferruginous)

Arenite (composed primarily of SiO2 with Fe2O3 staining)

Amethyst

SiO2 (Silicon Dioxide with Iron impurities)