Sedimentary (Secondary Classification For A Weathered Mineral Specimen)

Fluorite

Calcium Fluoride (CaF2)

Precious Opal

Hydrated Silica (SiO2·nH2O)

Jasper

Jasper (Silicon Dioxide, SiO2)

Chrysocolla in Matrix

Hydrated copper phyllosilicate (Cu,Al)2H2Si2O5(OH)4' nH2O on Quartz/Feldspar matrix

Quartz Pebble (Chalcedony/Agate)

Silicon Dioxide (SiO2)

Bumblebee Jasper

Calcite-Auripigment-Pyrite-Realgar assemblage (Carbonate/Sulphide mixture)

Chert (containing Orbicular/Agate patterns)

Microcrystalline Quartz (SiO2)

Sand (Construction Grade)

Unconsolidated siliciclastic sediment (primarily SiO2)

Green Calcite

Calcium Carbonate (CaCO3)

Chert (specifically tan/pink variety)

Silicon Dioxide (SiO2)

Limestone with Algal/Lichen Colonization

Calcium Carbonate (CaCO3)

Sandstone (with Iron Staining)

Clastic sedimentary rock (primarily SiO2 with Fe2O3 staining)

Citrine or Yellow Quartz

Silicon Dioxide (SiO2) with iron impurities

Magnetite / Iron Ore

Magnetite (Fe3O4)

Chert (often called Flint or Agate nodule)

Cryptocrystalline Quartz (SiO2)

Howlite and Purpurite druzy

Calcium Borosilicate Hydroxide (Howlite) and Manganese Phosphate (Purpurite)

Shale (possibly)

Shale (fine-grained clastic sedimentary rock)

Pyrite in Quartz

Iron Sulfide (FeS2) in Silicon Dioxide (SiO2)

Dalmatian Stone (commonly Dyed)

Dalmatian Jasper (Peralkaline igneous rock)

Chert (Grey Flint)

Silicon Dioxide (SiO2) - Microcrystalline Quartz

Fairburn Agate / Agate-bearing Breccia

Cryptocrystalline Quartz (SiO2) within Jasper/Breccia matrix

Sandstone (Water-worn Pebble)

Clastic Sedimentary Rock (primarily SiO2)

Quartz (Smoky or Clear variety with inclusions)

Silicon Dioxide (SiO2)

White Marble

Recrystallized Calcite (CaCO3)

Ruby

Corundum (Al2O3) with Chromium traces

Agatized Fossil (Druzy Agate)

Silicon Dioxide (SiO2) replacing organic matter

River Rock (Basalt/Greywacke)

Aphanitic Basalt or Lithic Sandstone (Greywacke)

Pyrite

Iron Sulfide (FeS2)

Quartz Geode (partially formed)

Silicon Dioxide (SiO2)

Clear Quartz Crystal Cluster

Silicon Dioxide (SiO2)

Ferruginous Quartz

Silicon Dioxide (SiO2) with iron oxide inclusions (Limonite/Goethite)

Pyrite in Matrix (Fool's Gold)

Iron Disulfide (FeS2)

Sandstone (Ferruginous)

Arenite (primarily SiO2 with Fe2O3 staining)

Chert (with Quartz Vein)

Chert (Siliceous sedimentary rock, predominantly Microcrystalline Quartz SiO2)

Sandstone (likely Quartzose Sandstone)

Arenite (composed primarily of SiO2)

Sandstone (Ferruginous)

Arenite with Iron Oxide cement

Wonderstone (Liesegang Sandstone)

Silicified Sandstone with Liesegang Rings (SiO2 + FeO(OH))

White Opal (Common)

Hydrated Silica (SiO2·nH2O)

Jasper

Silicon dioxide (SiO2)

Fluorite

Calcium Fluoride (CaF2)

Sandstone (with carbonaceous plant fragments)

Arenite (composed primarily of SiO2)

Milky Quartz (Ferruginous variety)

Silicon Dioxide (SiO2)