Multiple

Botryoidal Hematite (Kidney Ore)

Iron(III) oxide (Fe2O3)

Quartzite Cobble

Quartzite (SiO2)

Mixed Tumbled Stones Collection

Mixed Silicates and Carbonates (Quartz, Amorphous Silica, Carbonates)

Botryoidal Chalcedony

Silicon Dioxide (SiO2)

Quartz with Mafic/Chlorite Veins

Silicon Dioxide (SiO2) with Chlorite/Epidote cross-veining

Quartzite Pebble

Meta-quartzite (SiO2)

Quartzite River Pebble

Quartzite (comp: SiO2)

Quartz Pebble

Quartz (Silicon Dioxide, SiO2)

Uncertain polished mineral specimen

Indeterminate; possibly quartz or feldspar with iron-oxide staining

Aragonite Star Cluster

Aragonite (Calcium Carbonate, CaCO3)

River-rounded landscaping pebbles

Mixed alluvial gravel; commonly quartzite, granite, basalt, sandstone, and quartz

Quartz Pebble

Silicon Dioxide (SiO2)

Quartz Veined Mudstone

Metasedimentary rock with Quartz (SiO2) veins

Quartzite pebble

Metamorphic Quartzite (SiO2)

Quartzite Cobble

Metamorphic Rock (SiO2 dominated)

Zircon

Zircon (Zirconium Silicate, ZrSiO4)

Jasper (likely Polychrome or Ocean Jasper)

Silicon Dioxide (SiO2) with impurities

Mixed river gravel (alluvial conglomeratic sediment)

Polymictic alluvium; composition includes quartz, feldspar, chert, granite, basalt, and metamorphic rock fragments

Quartz Pebble

Silicon Dioxide (SiO2)

Quartzite (River Cobble)

SiO2 (Quartz-rich Metamorphic Rock)

River Quartzite Slik

Quartzite (SiO2)

Quartzite pebble

Quartzite (SiO2)

Mixed collection of common river stones

Varied lithologies, visibly including quartz-rich rock, dark mafic rock, sandstone, and purple quartz-bearing material

Botryoidal Chalcedony / Quartz

Silicon Dioxide (SiO2)

Red Jasper

Microcrystalline Quartz (SiO2) with Hematite impurities

Quartzite Cobble

Quartzite (SiO2)

Quartzite (River Cobble)

Quartzite (SiO2)

Lapis Lazuli

Lapis Lazuli (Mineral composition: Lazurite, Calcite, Sodalite, and Pyrite)

Limonite (Iron Ore)

FeO(OH)·nH2O (Hydrated Iron Oxide)

Quartzite (with Quartz Veining)

Quartzite (SiO2)

Sand Grain (Quartz)

Silicon Dioxide (SiO2)

Chert with Calcite Veins

Silicon Dioxide (SiO2) with Calcium Carbonate (CaCO3) intrusions

Lapis Lazuli

Lapis Lazuli (Complex silicate rock containing Lazurite (Na,Ca)8(AlSiO4)6(S,Cl,SO4,OH)2, Calcite, and Pyrite)

Conglomerate (pebble-to-cobble gravel)

Polymictic conglomerate; clast-supported conglomerate in a sandy or silty matrix

Quartzite River Cobble

Quartzite (primarily SiO2)

Riverstone (Quartzite Pebble)

Quartzite (primarily SiO2)

Lapis Lazuli (polished cabochon)

Lazurite-rich metamorphic rock (approx. Na6Ca2Al6Si6O24(SO4,S,Cl)2)

Lapis Lazuli

Sodium aluminum silicate with sulfur (main component: Lazurite [(Na,Ca)8(AlSiO4)6(SO4,S,Cl)2])

Lapis Lazuli

Na8[Al6Si6O24]n(S,Cl,SO4,OH)2

Mixed stream gravel and common rock specimens

Predominantly quartz-rich granitoid, quartzite, sandstone, shale/slate, and mafic volcanic fragments; exact species cannot be determined confidently from the image

Botryoidal Chalcedony (Agate)

Silicon Dioxide (SiO2)

Botryoidal Chalcedony (Agate)

Silicon Dioxide (SiO2)