Mineral, Often A Rock Given Its Aggregate Nature

Sandstone Pebble

Arenite (Siliclastic sedimentary rock)

Quartz

Quartz (SiO₂)

Greywhacke (River Pebble)

Graywacke (immature sandstone)

Purple Lava Rock / Vesicular Basalt

Vesicular Basalt (Mafic Extrusive Igneous Rock)

Shale

Lutaceous sedimentary rock

Smoky Quartz

Silicon Dioxide (SiO2)

Coquina / Shelly Sandstone

Calcareous Sandstone / Coquina

Banded Agate (with Quartz Geode Center)

Silicon Dioxide (SiO2)

Shale

Shale (clastic sedimentary rock)

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

Pink Rhodonite

Rhodonite (Manganese Iron Magnesium Calcium Silicate - (Mn,Fe,Mg,Ca)SiO3)

River Rock (River Cobbles)

Fluvial Conglomerate Clasts (primarily composed of various minerals such as Quartz, SiO2)

Shale

Shale (Lutite)

Jasper

Microcrystalline Quartz (SiO2)

Scoria

Extrusive Basaltic Scoria

Milky Quartz

Silicon Dioxide (SiO2)

Sandstone

Clastic Sedimentary Rock

Iron Slag

Ferrous slag (primarily silicates and oxides of calcium, iron, and magnesium)

Poppy Jasper

Microcrystalline Quartz (SiO2) with mineral inclusions

Banded Agate (specifically Carnelian Agate color)

Silicon Dioxide (SiO2) - variety of Chalcedony

Sandstone (Ferruginous)

Arenite (Siliclastic Sedimentary Rock)

Banded Rock (likely Quartz-rich)

Uncertain, likely a Metamorphic Rock (e.g., Gneiss or Schist) with prominent Quartz and other minerals

Green Quartz / Chrysoprase / Sea Glass

Silicon Dioxide (SiO2)

Shale or Mudstone River Pebble

Argillaceous sedimentary rock

Grey Agate (Tumbled)

Silicon Dioxide (SiO2)

Chrysocolla in Matrix

Cu2-xAlx(H2-xSi2O5)(OH)4·nH2O (Silicate/Secondary Copper Mineral)

Nephrite Jade (or Serpentine)

Nephrite (a variety of amphibole mineral tremolite-actinolite) or Serpentine Group minerals

Shale

Shale (Argillaceous sedimentary rock)

Jasper

Silicon dioxide, SiO2

Chalcedony (Banded/Mottled Variety)

Chalcedony (a cryptocrystalline variety of Quartz, SiO2)

Shale

Laminated Mudstone

Pumice (or Volcanic Tuff / Ash)

Pumice / Pyroclastic rock

Sandstone (Quartzose)

Arenite (primarily SiO2)

Milky Quartz Pebble

Quartz (Silicon Dioxide, SiO2)

Howlite and Purple Amethyst Druzy

Calcium Borosilicate Hydroxide (Howlite) and Silicon Dioxide (Quartz/Amethyst)

Red Jasper

Jasper (Silica with Hematite inclusions), SiO2

Dyed Agate Slice

Silicon Dioxide (SiO2)

Rough Topaz

Aluminum silicate fluoride hydroxide [Al2SiO4(F, OH)2]

Limestone

Calcium Carbonate (CaCO3)

Basalt

Basalt (Mafic volcanic rock)

Druzy Quartz

Crystalline Silicon Dioxide (SiO2)

Stream-Rounded Shale or Mudstone

Argillaceous sedimentary rock