Igneous And Metamorphic Derivative (Weathered)

Ironstone Concretion / Limonite Node

Goethite and Limonite (FeO(OH) nH2O)

Chert Pebble

Microcrystalline or cryptocrystalline Quartz (SiO2)

Rutilated Quartz

Quartz (SiO2) with Rutile (TiO2) inclusions

Chert (Iron-stained)

Microcrystalline silica (SiO2) with trace Iron oxide (Fe2O3)

Chert (Nodule)

Silicon Dioxide (SiO2)

Lake Superior Agate

Silicon Dioxide (SiO2) - Variety Agate

Carnelian

Carnelian Chalcedony (SiO2 with iron oxide impurities)

Chert (Nodule)

Chert (Silicon Dioxide, SiO2)

Limonite (Iron Ore)

Limonite (FeO(OH)·nH2O)

Dendritic Agate

Silicon Dioxide (SiO2) with Manganese/Iron oxide inclusions

Moqui Marble (Ironstone Concretion)

Goethite/Hematite Concretion (Fe2O3 / FeO(OH))

Limonite (Iron Ore)

Limonite (Hydrous iron(III) oxide-hydroxide mixture, primarily FeO(OH)·nH2O)

Banded Agate / Lace Agate

Agate (Silica/Quartz) - SiO2

Red Jasper

Silicon Dioxide (SiO2) with Hematite inclusions

Aragonite / Calcite Geode

Calcium Carbonate (CaCO3)

Ironstone with Limonite/Goethite coating

Ferruginous Sedimentary Rock (contains Limonite FeO(OH)·nH2O)

Limonite

FeO(OH)·nH2O (Hydrated iron oxide)

Quartz Pebble

Silicon Dioxide (SiO2)

Limonite (Yellow Ochre)

Hydrated iron(III) oxide-hydroxide (FeO(OH)·nH2O)

Garnet

Garnet Group (complex nesosilicates with general formula X3Y2(SiO4)3, where X can be Ca, Mg, Fe2+, Mn2+ and Y can be Al, Fe3+, Cr3+, V3+)

Quartzite

Quartzite (SiO2)

Quartzite

Metamorphosed Quartz Sandstone (SiO2)

Chert (Field Stone)

Microcrystalline / Cryptocrystalline Quartz (SiO2)

Chert (River Pebble)

Microcrystalline quartz (SiO2)

Ferruginous Siltstone or Mudstone

Ferruginous Siltstone / Goethitic Sandstone

Chert (Jasper/Agate variety)

Microcrystalline Quartz (SiO2)

Basalt with Iron Oxidation

Extrusive Mafic Igneous Rock (composed of Plagioclase and Pyroxene)

Turquoise

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

Ironstone (likely Limonite or Goethite)

Ferruginous sedimentary rock (FeO(OH)·nH2O)

Chert (Field Stone)

Chert (Silicon Dioxide, SiO2)

Turquoise (Rough)

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

Turquoise

Hydrous phosphate of copper and aluminum (CuAl6(PO4)4(OH)8·4H2O)

Green Chalcedony (likely Chrysoprase or Green Onyx)

Silicon Dioxide (SiO2) with trace nickel or chromium inclusions

Chalcedony (Agate Nodules)

Silicon Dioxide (SiO2)

Quartz Pebble

Silicon Dioxide (SiO2)

Limonite with Iron Inclusions

Limonite (Hydrated Iron Oxide, FeO(OH)·nH2O)

Chert (Jasper influence)

Microcrystalline Quartz (SiO2)

Psilomelane (Manganese Ore)

Psilomelane (Ba,H2O)2Mn5O10

Moss Agate

Silicon Dioxide (SiO2) with inclusions of Manganese or Iron oxide

Quartz Pebble

Silicon Dioxide (SiO2)

Gneiss (with Mica and Quartz)

Gneissic Metamorphic Rock

Green Aventurine

Aventurine (a variety of Quartz, SiO2 with fuchsite inclusions)