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

Pink Granite Porphyry Cobble

Porphyritic K-Feldspar Granite

Chert (and Petrified Wood)

Silicon Dioxide (SiO2)

Amethyst (Raw Quartz)

Amethyst (Silicon Dioxide with Iron impurities, SiO2)

Basalt with Quartz Veins

Basalt (complex silicate) with Quartz (SiO2) intrusions

Gneiss

Gneiss (High-grade regional metamorphic rock)

Quartzite

Quartzite (primarily SiO2)

Sandstone Concretion

Clastic Sedimentary Rock (primarily SiO2 with mineral cement)

Fossil Bivalve Shell

Class Bivalvia (e.g., Veneriidae family)

Clear Quartz

Silicon dioxide (SiO2)

Zebra Jasper (Zebra Stone)

Silicon Dioxide (SiO2) with iron oxide and manganese inclusions

Quartzite

Quartzite (primarily SiO2)

Brown Jasper

Silicon Dioxide (SiO2) with iron oxide inclusions

Conglomerate

Conglomerate (clastic sedimentary rock)

Quartz Veined Basalt

Mafic Volcanic Rock with Microcrystalline Quartz (SiO2)

Chert Pebble / Brachiopod Fossil Internal Mold

Silicon Dioxide (SiO2) / Fossil: Brachiopoda (generic internal mold)

Ferruginous Breccia

Breccia with Iron-rich (Hematite/Goethite) Matrix

Flowerstone

Porphyritic Basalt or Porphyritic Andesite

Epidote

Epidote (Ca2(Al2,Fe)(SiO4)(Si2O7)O(OH))

Chert (Green Jasperiod)

Chert (Microcrystalline Quartz, SiO2)

Quartz (Vein Quartz)

Silicon Dioxide (SiO2)

Granite

Phaneritic Felsic Intrusive Igneous Rock

Limestone

Calcium Carbonate (CaCO3)

Milky Quartz (Tumbled/Water-worn)

Silicon Dioxide (SiO2)

Dyed Agate Geode (Pink/Magenta)

Silicon Dioxide (SiO2) - variety of Chalcedony/Quartz

Quartz (Milky Quartz)

Silicon Dioxide (SiO2)

Limestone

Calcium Carbonate (CaCO3)

Chert (Nodule)

Chert (SiO2)

Snowflake Obsidian

Volcanic glass containing Spherulite inclusions (primarily Cristobalite, SiO2)

Blue Calcite

Calcium Carbonate (CaCO3)

Limestone

Calcium Carbonate (CaCO3)

Sandstone (Ferruginous)

Arenite (primarily SiO2 with Fe2O3 staining)

Quartz Pebble

Silicon Dioxide (SiO2)

Red Jasper

Silicon Dioxide (SiO2) with iron oxide inclusions

Lepidolite

Lepidolite (K(Li,Al)3(Al,Si,Rb)4O10(F,OH)2)

Quartz (Microcrystalline/Chert)

Silicon Dioxide (SiO2)

Milky Quartz (with trace inclusions)

Silicon Dioxide (SiO2)

Limestone

Calcium Carbonate (CaCO3)

Chert (Chert / Flint variety)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Quartz Pebble

Silicon Dioxide (SiO2)

Jasper (specifically Bloodstone/Heliotrope or Dark Green Jasper)

Cryptocrystalline Quartz (SiO2) with inclusions

Chert (Nodule)

Silicon Dioxide (SiO2) - Microcrystalline Quartz

Milky Quartz Pebble

Quartz (Silicon Dioxide, SiO2)