Organic (Often Found By Beachcombers)

Blue Star Sapphire

Corundum (Al2O3)

Milky Quartz (Common Quartz)

Quartz (Silicon Dioxide, SiO2)

Synthetic Marbled Aggregate (Footwear Component)

Ethylene-vinyl acetate (Croslite™)

Banded Agate (Lace Agate)

Agate (Variety of Cryptocrystalline Quartz), SiO2

Quartzite Cobble

Metamorphosed Quartz Sandstone (primarily SiO2)

Jasper (Red/Brown)

Silicon Dioxide (SiO2) with iron oxide inclusions

Vesicular Basalt with Opal or Quartz

Vesicular Basalt (Amorphous SiO2.nH2O if Opal)

Chrysocolla

Chrysocolla; (Cu,Al)2H2Si2O5(OH)4·nH2O

Magnetite / Iron Ore

Magnetite (Fe3O4)

Quartzite River Pebbles

Quartzite (primarily SiO2)

Quartzite

Quartzite (primarily SiO2)

Serpentine

Serpentinite (rock) containing serpentine minerals (e.g., Antigorite, Lizardite, Chrysotile)

Magnetite / Hematite mix (Iron Ore)

Fe3O4 (Magnetite) / Fe2O3 (Hematite)

Fluorite (Rainbow Fluorite)

Calcium Fluoride (CaF2)

Yellow Quartz Pebble (Citrine or Iron-stained Quartz)

Silicon Dioxide (SiO2)

Nephrite Jade

Nephrite (Ca2(Mg, Fe)5Si8O22(OH)2)

Turquoise

Hydrated phosphate of copper and aluminium [CuAl6(PO4)4(OH)8·4H2O]

Granite

Phaneritic Igneous Rock (Granitic)

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

Jasper (Red Chert)

Jasper (Silicon Dioxide, SiO2)

Gneiss (Cobble)

Gneiss

White Topaz

Aluminum Silicate Fluoride Hydroxide; Al2SiO4(F,OH)2

Milky Quartz with Iron Oxide Staining

Quartz (Silicon Dioxide, SiO2)

Blue Quartzite

Blue Quartzite (Primary mineral: Quartz, SiO2 with magnesio-riebeckite or crocidolite inclusions)

Pegmatite with Smoky Quartz and Feldspar

Pegmatite (Quartz: SiO2, Feldspar: KAlSi3O8)

Sodalite

Na8(Al6Si6O24)Cl2

Smoky Quartz (Rough Specimen)

Silicon Dioxide (SiO2)

Greenstone

Metamorphosed Mafic Igneous Rock

Milky Quartz

Silicon Dioxide (SiO2)

Milky Quartz with Iron Staining

Quartz (Silicon Dioxide, SiO2)

Smoky Quartz

Silicon Dioxide (SiO2)

Sandstone (with Concretion)

Arenite / Quartzose Sandstone

Serpentinite

Serpentinite (composed primarily of Serpentine group minerals: (Mg,Fe)3Si2O5(OH)4)

Rose Quartz

Silicon Dioxide (SiO2) with trace amounts of titanium, iron, or manganese

Amazonite in Matrix

Potassium Feldspar (Microcline), KAlSi3O8

Malachite

Copper carbonate hydroxide, Cu2CO3(OH)2

Milky Quartz

Silicon Dioxide (SiO2)

Azurite and Malachite on Matrix

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

Quartz (Milky/Smoky variety on matrix)

Silicon Dioxide (SiO2)

Blue Chalcedony

Silicon Dioxide (SiO2)

Chrysocolla on Matrix

Hydrated copper phyllosilicate (Cu,Al)2H2Si2O5(OH)4·nH2O

Serpentine

Serpentinite (rock), Serpentine group minerals (e.g., Antigorite, Lizardite, Chrysotile)