Limonite Concretion
Limonite (FeO(OH)·nH2O) Pseudomorph
sedimentary
Category
Mineral Variant
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Limonite (Iron Ore)
Hydrated ferric oxide mixture (FeO(OH)·nH2O)
sedimentary
Red Sandstone (Iron-stained)
Clastic sedimentary rock (primarily Quartz with Iron Oxides)
sedimentary
Turquoise
Hydrated phosphate of copper and aluminium - CuAl6(PO4)4(OH)8·4H2O
mineral
Limonite (Iron Ore)
Limonite (FeO(OH)·nH2O)
mineral
Polished bumblebee jasper bead
Bumblebee jasper (trade name); chiefly calcite, aragonite, and pyrite, with variable realgar/orpiment and other minerals
mineral
Weathered granite or granitic gneiss
Granite; chiefly quartz, feldspar, and mica, possibly with gneissic foliation
igneous
Garden Quartz (Lodalite)
Silicon Dioxide with various mineral inclusions (SiO2)
mineral
Polished agate geode slice
Microcrystalline quartz (chalcedony), SiO₂, with possible quartz-lined or calcite-filled cavity
mineral
Likely granitic gneiss pebble
Quartz–feldspar–biotite gneiss (visual identification; exact type uncertain)
metamorphic
Mica Schist / Granite
Mica Schist (Silicate metamorphic rock)
metamorphic
Fluorite
Calcium Fluoride (CaF2)
mineral
Limonite (Iron Ore / Ochre)
Hydrated iron(III) oxide-hydroxide (FeO(OH)·nH2O)
mineral
Limonite
FeO(OH)·nH2O
mineral
Selenite (variety of Gypsum)
Calcium sulfate dihydrate (CaSO4·2H2O)
mineral
Merlinite (dendritic opal)
Common opal (hydrated amorphous silica, SiO₂·nH₂O) with dark manganese-oxide dendrites; the trade name “merlinite” is also applied to other patterned stones.
sedimentary
Morganite and Aquamarine (Beryl) Bracelet
Beryllium aluminum silicate, Be3Al2(SiO3)6
gemstone
Bicolor Quartz Tumble
Silicon Dioxide (SiO2)
mineral
Green Fluorite
Calcium Fluoride (CaF2)
mineral
Hematite
Iron(III) oxide (Fe2O3)
mineral
Hematite
Hematite (Iron(III) oxide, Fe2O3)
mineral
Native Copper Nugget
Native Copper (Cu)
mineral
Geode (Calcite or Quartz)
Silicon Dioxide (SiO2) or Calcium Carbonate (CaCO3)
sedimentary
Sandstone
Arenite
sedimentary
Blue Chalcedony
Silicon Dioxide (SiO2)
mineral
Pyrite (Fool's Gold)
Iron Sulfide (FeS2)
mineral
Epidote
Calcium aluminum iron silicate (Ca2(Al, Fe)3(SiO4)3(OH))
mineral
Basalt with Vesicular/Amygdaloidal Alteration
Extrusive Igneous Rock (Mafic)
igneous
Basalt with Amygdule
Aphanitic Mafic Volcanic Rock (Basalt) with Zeolite/Quartz Infill
igneous
Epidote
Epidote (Ca2(Al2,Fe3+)(SiO4)(Si2O7)O(OH))
mineral
Amphibolite
Amphibolite, composed mainly of amphibole and plagioclase feldspar
metamorphic
Blue Apatite
Fluoroapatite (Ca5(PO4)3F)
mineral
Weathered granite or granitic gneiss
Granite/granitic gneiss, composed mainly of quartz, feldspar, and mica
igneous
Orthoclase Feldspar
Orthoclase (KAlSi3O8)
mineral
Likely serpentinite (greenstone pebble)
Serpentinite, composed mainly of serpentine-group minerals (e.g., lizardite, chrysotile, or antigorite)
metamorphic
Biotite gneiss (probable)
Foliated quartz–feldspar–mica gneiss; commonly containing biotite mica, quartz, and plagioclase/alkali feldspar
metamorphic
Copper Ore
Mixed copper sulfides/oxides in gangue matrix
mineral
Gravel and Pebbles
Unconsolidated rock fragments / detrital sediment
sedimentary
Fossilized Shark Tooth
Chondrichthyes (Class)
fossil
Fossil Shark Tooth
Carcharodon or Carcharias fossil (Vertebrate Fossil)
sedimentary
Mica schist
Schist dominated by muscovite/biotite mica, commonly with quartz and feldspar
metamorphic
Weathered granite pebble
Granite, a coarse-grained felsic intrusive igneous rock
igneous