Tumbled milky quartz
Quartz (SiO₂), likely massive milky quartz
mineral
Category
Mineral Description (Anthropogenic Material)
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Silicified fossil-bearing limestone (likely chert/agate replacement)
Microcrystalline quartz (SiO₂) replacing carbonate rock; possible fossiliferous limestone
sedimentary
Sandstone (Quartzose)
Arenite (primarily SiO2)
sedimentary
Chalcopyrite (Peacock Ore)
Chalcopyrite (CuFeS2)
mineral
Note regarding image quality
Indeterminate
Polished tiger’s-eye
Quartz variety, chiefly fibrous quartz (SiO₂), with iron-oxide inclusions
mineral
Black tourmaline beads (likely schorl)
Schorl, NaFe₃Al₆(BO₃)₃Si₆O₁₈(OH)₄
mineral
Clear quartz crystal sphere
Quartz (silicon dioxide, SiO₂)
mineral
Polished brecciated jasper (likely orbicular/picture jasper)
Microcrystalline quartz/chalcedony (SiO₂) with iron-oxide staining and breccia fragments
mineral
Fulgurite
Lechatelierite (vitreous silica tube)
mineral
Chert (Flint Nodules)
Chert (Silicon Dioxide, SiO2)
sedimentary
Sandstone (Ferruginous)
Clastic sedimentary rock (SiO2 with Fe2O3)
sedimentary
Vesicular basalt (possibly amygdaloidal basalt)
Basalt, chiefly plagioclase feldspar and pyroxene, with possible olivine and secondary mineral infillings
igneous
Chert (Jasper/Chalcedony)
Microcrystalline Quartz (SiO2)
sedimentary
White Quartz Pebble
Crystalline Silicon Dioxide (SiO2)
mineral
Small seashell fossil or shell fragment
Likely calcium-carbonate shell material, chiefly aragonite or calcite; exact species indeterminate
fossil
Sandstone
Arenite (primarily Quartz-based Sandstone)
sedimentary
Sandstone (likely Quartzose Sandstone)
Arenite (SiO2 principal composition)
sedimentary
Diamond
Carbon (C)
gemstone
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
mineral
Raw green fluorite (probable)
Fluorite, calcium fluoride (CaF₂)
mineral
Moss Agate
Silicon Dioxide (SiO2) with inclusions
mineral
Granite Gneiss
Gneiss (High-grade metamorphic rock)
metamorphic
Petrified Wood
Silicified Wood (primarily SiO2)
sedimentary
Small polished brown stone
Indeterminate; possibly tumbled jasper, brown agate, or another iron-stained silicate
mineral
Ammonite Fossil
Ammonoidea
fossil
Quartz-rich breccia or altered granite fragment
Polymineralic quartz–feldspar rock, likely hydrothermally altered granite/pegmatite
igneous
Charoite
Charoite (Complex silicate mineral rock)
metamorphic
Diorite
Plutonic Igneous Rock (NaAlSi3O8, CaAl2Si2O8)
igneous
Serpentine
Hydrous magnesium iron silicate, (Mg,Fe)3Si2O5(OH)4
metamorphic
Limestone
Calcite (CaCO3)
sedimentary
Quartzite
Quartzite (SiO2)
metamorphic
Coquina
Biogenic Limestone (Calcium Carbonate, CaCO3)
sedimentary
Travertine (Tufa)
Chemical Sedimentary Rock / Travertine (CaCO3)
sedimentary
Green Aventurine
Aventurine Quartz (SiO2 with Fuchsite inclusions)
mineral
Sandstone
Arenite
sedimentary
Rose Quartz
Quartz (Silicon Dioxide, SiO2) with traces of Titanium, Manganese, or Iron
mineral
Sandstone
Arenite
sedimentary
Quartz Pebble
Crystalline Silica (SiO2)
sedimentary
Red Sandstone (Old Red Sandstone)
Ferruginous Sandstone (SiO2 + Fe2O3)
sedimentary
Weathered granite or granitic gneiss
Granite; primarily quartz, feldspar, and mica (possibly metamorphosed to gneiss)
igneous
Tumbled white chalcedony (milky agate)
Microcrystalline quartz, SiO₂; chalcedony, locally grading toward milky agate
mineral