Sedimentary Or Metamorphic

Green Opal

Hydrated Silica (SiO2·nH2O)

Quartz Vein in Hematitic Siltstone

Hydrothermal Quartz (SiO2) in Ferriferous Matrix

White quartz bead strand

Quartz, silicon dioxide (SiO₂), likely milky or translucent quartz; beads are polished and drilled

Red Jasper

Jasper (Silicon Dioxide Si₂O₃)

Ferruginous Quartz

Silicon Dioxide (SiO2) with Iron Oxide (Fe2O3) inclusions

Blue Apatite

Fluorapatite (Ca5(PO4)3F)

Weathered brown river pebble, likely sandstone or iron-rich quartzite

Indeterminate; probable quartz-rich sandstone (quartz and iron-oxide cement)

Gold-colored mineral specimen, likely pyrite or weathered mica schist

Tentatively pyrite (FeS₂); identification is uncertain from the obscured image

Beach Pebbles and Quartz Aggregates

Quartz pebbles and biogenic fragments (SiO2, CaCO3)

Milky Quartz

Silicon Dioxide (SiO2)

Quartz

Silicon Dioxide (SiO2)

Green Aventurine

Aventurine Quartz (SiO2 with inclusions of Fuchsite)

Likely tumbled quartz or chalcedony fragment

Quartz (SiO₂), possibly microcrystalline chalcedony

Quartz

Silicon Dioxide (SiO2)

Tumbled quartz-rich rock, possibly calcite or sandstone

Indeterminate from photograph; likely microcrystalline quartz (SiO₂) or calcite (CaCO₃)

Tumbled quartz-rich carbonate rock

Likely massive quartz (SiO₂), possibly calcite-bearing marble or limestone

Red coral (polished coral beads)

Corallium spp.; chiefly calcium carbonate (CaCO₃, calcite)

Quartz Vein in Host Rock (Likely Slate or Shale)

Hydrothermal Quartz (SiO2) in Pelitic host rock

Red Jasper

Jasper (Silicon Dioxide, SiO2)

Rounded quartz-rich river pebbles

Alluvial gravel; commonly quartzite, chert, and quartz-bearing sandstone fragments

Red Jasper

Jasper (Silicon Dioxide with Iron Oxide inclusions, SiO2)

Quartz (Milky Quartz / Quartzite)

Silicon Dioxide (SiO2)

Polished hematite bead (probable)

Hematite, Fe₂O₃

Quartz (Milky / Massive Quartz)

Silicon Dioxide (SiO2)

Quartz Vein in Sedimentary Matrix

Silicon Dioxide (SiO2) with host rock

Quartz Vein in Matrix (Breccia / Host Rock with Quartz)

Silicon Dioxide (SiO2) in Host Rock Matrix

Unidentified weathered rock fragments

Likely mixed silicate rocks; specific identification requires testing

Polished gemstone tower assortment

Primarily quartz varieties and simulants; apparent amethyst (SiO₂), rose quartz (SiO₂), clear quartz (SiO₂), fluorite (CaF₂), sodalite, malachite, and possibly dyed or composite stones

Small gold-colored mineral crystal, likely pyrite

Pyrite (FeS₂), tentatively; native gold is a less likely alternative

Pyrite

Iron Pyrite (FeS2)

Pyrite

Iron Sulfide (FeS2)

Quartz (Milky/Clear variety)

Silicon Dioxide (SiO2)

Pyrite in Quartz

Iron Sulfide (FeS2) on Silicon Dioxide (SiO2)

Clear Quartz

Silicon Dioxide (SiO2)

Quartz crystal (likely clear quartz)

Quartz, silicon dioxide (SiO₂)

Red Jasper

Silicon Dioxide (SiO2) with Iron Oxide inclusions

Red Jasper

Silicon Dioxide (SiO2) with iron oxide inclusions

Banded River Cobble with Mafic Dike

Hydrothermally altered Graywacke or Sandstone with Mafic Intrusion

Limonite (Iron Ore)

Limonite (an amorphous mixture of hydrated iron oxides, primarily FeO(OH)·nH2O)

Red Jasper (Quartzite)

Silicon Dioxide (SiO2) with iron oxide inclusions

Quartz-rich rock, possibly milky quartz or quartzite fragment

Quartz (SiO₂), potentially quartzite if metamorphic

Metallic sulfide mineral fragment, likely galena

Galena (lead sulfide, PbS), tentative identification