Gold Ore
Native Gold (Au)
Category
Browse sedimentary (chemically precipitated mineral) specimens identified by the Rock Identifier community.
Gold Ore
Native Gold (Au)
Limonite pseudo-concretion (Ironstone)
Limonite (FeO(OH)·nH2O) / Goethite
Pale limestone
Limestone, predominantly calcite (CaCO₃)
Likely red jasper or iron-rich chert
Microcrystalline quartz (SiO₂) colored by hematite/goethite
Chalky limestone fragment
Micritic limestone, chiefly calcite (CaCO₃)
Weathered iron-rich chert or jasper
Microcrystalline quartz (SiO₂), variably stained by iron oxides
Limonite (Iron Ore)
Hydrated iron(III) oxide-hydroxide (FeO(OH)·nH2O)
Weathered iron-rich rock, possibly hematite-bearing basalt or ironstone
Uncertain; likely Fe-oxide-rich basalt/ironstone containing hematite (Fe₂O₃), magnetite (Fe₃O₄), and silicate minerals
Quartz (Milky/Crystalline fragment)
Silicon Dioxide (SiO2)
Hematite
Hematite, Iron(III) oxide (Fe2O3)
Orange Calcite
Calcium Carbonate (CaCO3)
Red jasper (likely iron-rich chert)
Microcrystalline quartz, SiO₂, colored mainly by hematite/goethite
Red sandstone or iron-stained chert
Likely quartz-rich sandstone (SiO₂) or microcrystalline quartz/chert with hematite
Goethite/Hematite Nodule
Goethite (FeO(OH)) and Hematite (Fe2O3)
Chert
Chert (SiO2)
Green Calcite
Calcium Carbonate (CaCO3)
Limonite Concretion
Hydrated Iron Oxide-Hydroxide, FeO(OH)·nH2O
Orange Calcite
Calcium Carbonate (CaCO3)
Honey Calcite
Calcium Carbonate (CaCO3)
Yellow Calcite
Calcium Carbonate (CaCO3)
Limonite (Iron Ore)
Hydrated iron(III) oxide-hydroxide (FeO(OH)·nH2O)
Wonderstone Jasper
Silicon Dioxide (SiO2) with iron oxide inclusions
Chert (Nodular Chert)
Microcrystalline Quartz (SiO2)
Manganese Ore (Psilomelane/Pyrolusite)
Psilomelane ((Ba,H2O)2Mn5O10) and Pyrolusite (MnO2)
Limonite (Iron Ore)
Goethite and related iron hydroxides (FeO(OH)·nH2O)
Orange Calcite
Calcium Carbonate (CaCO3)
Limonite on Sandstone
Iron Oxyhydroxide (FeO(OH)·nH2O) on Quartz Sandstone
Honey Calcite
Calcium Carbonate (CaCO3)
Chert with Quartz Veining
Microcrystalline Silica (SiO2)
Hematite
Iron(III) oxide (Fe2O3)
Chalcedony with Druzy Quartz
Silicon Dioxide (SiO2)
Quartz pebble
Silicon Dioxide (SiO2)
Fairy Stone (Menilite Concretion)
Carbonate-rich concretion (often Siderite or Calcite in Clay)
Orange Calcite
Calcium Carbonate (CaCO3)
Chalcedony / Agate
Silicon Dioxide (SiO2)
Yellow Calcite
Calcium Carbonate, CaCO3
Celestite
Celestine (SrSO4)
Limonite or Ironstone Concretion
FeO(OH)·nH₂O (Hydrated iron oxide-hydroxide)
Orange Calcite
Calcite (Calcium Carbonate, CaCO3)
Fluorite
Calcium Fluoride (CaF2)
Blue Chalcedony
Chalcedony (cryptocrystalline Silicon Dioxide - SiO2)
Chert (with Quartz Veining)
Microcrystalline Quartz (SiO2)