Sedimentary (Chemically Precipitated) Or Metamorphic

Native Gold (in Jewelry)

Gold (Au)

Quartz (Milky/Clear)

Silicon Dioxide (SiO2)

Fossiliferous Limestone with Brachiopod

Limestone (Calcium Carbonate, CaCO3) with Phylum Brachiopoda fossil

Iron-rich concretion or weathered ironstone

Goethite–hematite-rich limonite (FeO(OH)·nH₂O / Fe₂O₃)

Weathered iron-rich concretion

Goethite–hematite limonite concretion, likely with quartz and clay minerals

Moqui Marbles

Ironstone Concretions (Hematite / Goethite / Sandstone)

Jasper

Microcrystalline Quartz (SiO2)

Fossiliferous Limestone with Rugose Coral

Calcite (CaCO3) containing a Rugosa (Horn Coral) fossil

Ferruginous Sandstone

Arenite with limonite/goethite cement

Ocean Jasper

Orbicular Jasper (Silicon Dioxide SiO2)

Quartzite

Metamorphic Rock (Mainly SiO2)

Sapphirine in Matrix

Sapphirine (Mg,Al)8(Al,Si)6O20

Quartzite

Metamorphic Quartzite (SiO2)

Quartzite

Metamorphic Quartzite (SiO2)

Banded Calcite (Mexican Onyx)

Calcium Carbonate (CaCO3)

Honey calcite (yellow calcite)

Calcite, calcium carbonate (CaCO₃)

Quartz-bearing sulfide ore, possibly pyrite in altered host rock

Likely pyrite (FeS₂) with quartz and possibly calcite or carbonate gangue; exact identification requires testing

Quartzite

Quartzite (Metamorphic Quartz Sandstone)

Calcite (likely chalky calcite fragment)

Calcite, calcium carbonate (CaCO₃)

Hematite

Iron(III) oxide (Fe2O3)

Quartz Pebble

Silicon Dioxide (SiO2)

Tumbled limestone or marble

Calcite-rich carbonate rock; likely limestone (CaCO₃), possibly marble

Yellow Ochre / Limonite

Limonite (FeO(OH)·nH2O)

Garnet in Host Rock

Garnet Group (A3B2(SiO4)3)

Iron-rich chert or jasper

Microcrystalline quartz (SiO₂), variably stained by iron oxides/hydroxides

Septarian Nodule (Dragon Stone)

Septarian Concretion (CaCO3 + CaMg(CO3)2 + SiO2)

Ferruginous Breccia

Breccia with Iron-rich (Hematite/Goethite) Matrix

Quartzite with Quartz Vein

Quartzite (primarily SiO2)

Veined Grey Metamorphic Pebble

Quartzo-feldspathic vein in Metabasalt / Serpentinite / Slate

Quartzite

Quartzite (primarily SiO2)

Quartz vein fragment

Milky quartz (SiO₂), possibly with weathered host rock

Banded Chert

Chert (Silicon Dioxide, SiO2)

Quartz (Milk or Clear Variety)

Silicon Dioxide (SiO2)

Quartzite with Quartz Veining

Quartzite (primarily SiO2)

Iron-rich concretion (probable limonite/goethite concretion)

Hydrated iron oxides, chiefly limonite (FeO(OH)·nH₂O) and goethite (FeO(OH))

Septarian Nodule (Micro-fragment)

Septarian Nodule / Concretion (CaCO3 + CaMg(CO3)2 + Quartz)

Small tumbled quartz pebble, possibly chalcedony

Quartz (SiO₂), likely microcrystalline chalcedony

Clear Quartz (Rock Crystal)

Silicon Dioxide (SiO2)

Quartz (Milky/Common variant)

Silicon Dioxide (SiO2)

Quartz (Clear Quartz/Rock Crystal)

Silicon Dioxide (SiO2)

Pyrite on Quartz

Iron Sulfide (FeS2) on Silicon Dioxide (SiO2)

Quartzite

Quartzite (SiO2)