Magnetite
Magnetite (Fe3O4)
Category
Browse organic (often found by beachcombers) specimens identified by the Rock Identifier community.
Magnetite
Magnetite (Fe3O4)
Quartzite Cobble
Quartzite (SiO2)
Quartzite Pebbles
Quartzite (primarily SiO2)
Goethite (likely as part of Limonite/Ironstone)
Goethite (α-FeOOH)
Chert (Iron-stained)
Microcrystalline Quartz (SiO2)
Lepidolite
K(Li,Al)3(Al,Si,Rb)4O10(F,OH)2
Jasper (likely Brecciated or Multi-colored)
Jasper (SiO2)
Fluorite
Calcium Fluoride (CaF2)
Rhodonite
Manganese Inosilicate (Mn,Fe,Mg,Ca)SiO3
Quartzite Pebble
Quartzite (SiO2)
Fuchsite
Chromium-rich Muscovite (K(Al,Cr)2(AlSi3O10)(OH)2)
Iron-stained Quartzite
Quartzite with Limonite/Hematite staining (SiO2 with FeO(OH)·nH2O)
Chert Nodule
Microcrystalline Quartz (SiO2)
Picture Jasper
Silicon Dioxide (SiO2) with iron oxide inclusions
Brecciated stone pebble
Breccia
Lepidolite Polished Point
Lepidolite (K(Li,Al)3(Al,Si,Rb)4O10(F,OH)2)
Magnetite
Magnetite (Fe3O4)
Quartzite
Quartzite (primarily SiO2)
Chert (or Jasper)
Microcrystalline Quartz (SiO2)
Mosasaur Tooth
Mosasauridae (likely Prognathodon or Enchodus sp.)
Pumice or Tuff
Pumice / Tuff
Rhodonite
Rhodonite (MnSiO3)
Amber
Amber (Fossilized Tree Resin)
Coprolite
Fossilized feces (various taxa)
Quartzite Pebble
Metamorphosed Quartz Sandstone (SiO2)
Banded Calcite (Mexican Onyx)
Calcium Carbonate (CaCO3)
Ruby
Corundum (Al2O3 with Chromium impurities)
Terrazzo (Man-made Composite)
Cementitious or Resin-bound Lithic Composite
Quartzite
Quartzite (primarily SiO2)
Green Aventurine
Silicon Dioxide with Fuchsite inclusions (SiO2 + K(Al,Cr)2AlSi3O10(OH)2)
Hemimorphite
Hemimorphite (Zn4Si2O7(OH)2·H2O)
Sodalite
Sodalite (Na8Al6Si6O24Cl2)
Jasper (likely a variety of Brecciated Jasper or a patterned variety)
Silicon dioxide (SiO2)
Blue Quartz
Quartz (SiO2) with inclusions
Agate
Agate (a variety of Chalcedony, SiO2)
Limestone
Calcium Carbonate (CaCO3)
Quartzite
Quartzite (Silicon Dioxide, SiO2)
Chalcopyrite
Chalcopyrite (CuFeS2)
Fossil Rugose Coral (Horn Coral)
Order Rugosa
Pink Aragonite
CaCO3
Quartzite (River Pebble)
Metamorphic Quartzite (primarily SiO2)
Rose Quartz
Quartz (SiO₂), variety Rose Quartz