Gold Nugget (Placer Gold)
Native Gold (Au)
Category
Browse organic (often found by beachcombers) specimens identified by the Rock Identifier community.
Gold Nugget (Placer Gold)
Native Gold (Au)
Orange Calcite
Calcite (Calcium Carbonate, CaCO3)
Fossilized Rugose Coral (Horn Coral)
Rugosa (Order) - often Grewingkia or Zaphrenthis
Ferruginous Quartz
Silicon Dioxide (SiO2) with Hematite/Limonite impurities
Diabase (also known as Dolerite)
Diabase / Microgabbro
Quartzite pebble
Quartzite (SiO2)
Quartzite Pebbler
Quartzite (mainly SiO2)
Chert (Pink and Yellow Chert)
Microcrystalline Quartz (SiO2)
Granite
Granitoid (dominated by Quartz and Feldspar)
Crazy Lace Agate
Agate (Chalcedony), SiO2
Fossilized Shark Tooth (Otodus obliquus)
Otodus obliquus (Mineral: Fluorapatite)
Chert
Microcrystalline Quartz (SiO2)
Red Jasper
Silicon Dioxide (SiO2) with Hematite impurities
Agate (specifically Botswana or Lake Superior style chalcedony)
Silicon Dioxide (SiO2)
Clear Quartz
Silicon Dioxide (SiO2)
Red Jasper
Silicon Dioxide (SiO2) with Hematite impurities
Sandstone or Mudstone with Iron Staining
Ferruginous Sandstone/Mudstone
Milky Quartz
Silicon Dioxide (SiO2)
Banded Chalcedony (Agate)
Silicon Dioxide (SiO2)
Banded Agate (Onyx type)
Silicon dioxide (SiO2)
Agate
SiO2
Banded Agate
Cryptocrystalline Quartz (SiO2)
Fuchsite
K(Al,Cr)2(AlSi3O10)(OH)2
Sandstone
Arenite
Sandstone
Arenite (SiO2 principal)
Quartz Pebble
Silicon Dioxide (SiO2)
Gold Flakes in Oil (Novelty Specimen)
Native Gold (Au)
Red Quartzite River Stone
Metamorphic Rock (composed mainly of Quartz, SiO2)
Quartzite
Quartzite (SiO2)
Citrine (likely Heat-Treated)
Quartz (Silicon Dioxide, SiO2)
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
Stichtite in Serpentine (Atlantasite)
Mg6Cr2CO3(OH)16·4H2O in Mg3Si2O5(OH)4
Agate Nodule / Weathered Chert
SiO2 (Silicon Dioxide - Microcrystalline Quartz)
Sandstone (likely Siltstone or Mudstone variety)
Clastic Sedimentary Rock (primarily SiO2 with iron oxides)
Peridot
Olivine ((Mg, Fe)2SiO4)
Cubic Zirconia (Faceted)
Zirconium Dioxide (ZrO2)
Chert (with Limestone matrix)
Microcrystalline Quartz (SiO2)
Quartzite Pebble
Quartzite (mostly SiO2)
Moqui Marble (Iron-Oxide Concretion)
Iron Oxide Concretion (Fe2O3)
Amazonite
Microcline (variety Amazonite), K(AlSi3O8)
Jasper (Red Jasper)
Silicon Dioxide (SiO2) with Hematite inclusions
Bornite
Copper Iron Sulfide (Cu5FeS4)