Iron-rich concretion or slag-like mineral fragment
Likely limonite/goethite (FeO(OH)·nH₂O), possibly magnetite-bearing material
mineral
Category
Industrial Byproduct (Anthropogenic Material)
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Likely slag or metallic industrial byproduct
Unidentified iron-rich ferrous slag; possibly magnetite-bearing slag
mineral
Chert (Arrowhead/Projectile Point)
Cryptocrystalline Quartz (SiO2)
sedimentary
Chert (Arrowhead Fragment)
Microcrystalline Quartz (SiO2)
sedimentary
Concrete-like aggregate surface with embedded rock fragments
Anthropogenic concrete or exposed aggregate; not a natural rock specimen
sedimentary
Green sea glass (likely)
Anthropogenic glass, not a mineral; composition commonly soda–lime silicate glass
mineral
Chert (Arrowhead/Tool variety)
Microcrystalline Quartz (SiO2)
sedimentary
Note: Item is not a geological specimen
Polyester mesh and Ethylene-vinyl acetate (EVA) polymer
Synthetic / Anthropogenic Material
Painted River Rock
Artificially Coated Sedimentary Rock
sedimentary
Sea Glass
Man-made silicate glass
mineral
Quartz (Milky/River Quartz)
Silicon Dioxide (SiO2)
mineral
Likely weathered iron-rich rock or slag fragment
Indeterminate; possibly limonite/goethite-bearing rock (FeO(OH)·nH₂O) or industrial iron slag
mineral
Sea Glass
Man-made silicate glass
mineral
Chert / Flint Handaxe
Cryptocrystalline Quartz (SiO2)
sedimentary
Sandstone-based Concrete Fragment
Cementitious Composite with Sedimentary Aggregate
sedimentary (man-made/anthropogenic)
Asphalt (Bituminous Concrete)
Bituminous mix containing aggregates and petroleum-based binder (CnH2n+2)
not a rock (anthropogenic material/technofossil)
Dark polished stone, likely basalt or slag-like volcanic rock
Probable fine-grained basalt; exact identification requires testing
igneous
Sea Glass (Frosted Glass Fragment)
Amorphous Silica (Anthropogenic Sediment)
sedimentary
Chert (Arrowhead Preform or Point)
Chert (Microcrystalline Quartz, SiO2)
sedimentary
Asphalt fragment
Bituminous concrete
anthropogenic material
Blue Sea Glass
Amorphous Silica (Anthropogenic glass)
not a rock (man-made origin)
Fired Clay Brick (Anthropic Rock substitute)
Anthropogenic polycrystalline ceramic (predominantly Mullite and Quartz: Al6Si2O13 + SiO2)
metamorphic (man-made / anthropic)
Weathered metallic sulfide ore, likely pyrite-bearing rock
Pyrite (FeS₂), possibly in a quartz–iron-oxide host
mineral
Ambergris
Ambra grisea (Metabolic byproduct)
Organic (Geological relative)
Tiffany Stone
Bertrandite-Bearing Fluorite Hyalite Opal
metamorphic
Green Obsidian Sphere (man-made glass)
Vitreous Silica with Chromium/Iron additives
mineralogical simulant
Asphalt (Road Aggregate)
Bituminous Conglomerate / Asphalt Concrete
Anthropogenic (Man-made)
Chert (Arrowhead Fragment)
Silicon Dioxide (SiO2)
sedimentary
Pyrite in Matrix
Iron Sulfide (FeS2)
mineral
Quartzite Arrowhead (Archaeological Lithic)
Recrystallized Quartz (SiO2)
metamorphic
Chert Arrowhead
Cryptocrystalline Quartz (SiO2)
sedimentary
Mother of Pearl (Nacre)
Aragonite (CaCO3) with Organic Matrix
mineral
Fluorite
Calcium fluoride (CaF2)
mineral
Chert Arrowhead (Projectile Point)
Chert (Cryptocrystalline Quartz, SiO2)
sedimentary
Bismuth
Bismuth (Bi)
mineral
Iron-rich vesicular rock, possibly slag or weathered basalt
Identification uncertain; likely ferruginous basalt/ironstone, with possible anthropogenic iron slag
igneous
Silver (Native Element)
Ag (Argentum)
mineral
Nutting Stone / Cupstone (Sandstone or Quartzite)
Sedimentary rock with anthropogenic modification (cupule)
sedimentary
Crackled Quartz (Blue Dyed)
Silicon Dioxide (SiO2) with anthropogenic dye
mineral
Chert Arrowhead
Microcrystalline Quartz (SiO2)
sedimentary
Blue Dyed Quartzite
Silicon Dioxide (SiO2) with artificial pigment
metamorphic
Sea Glass
Man-made silicate glass weathering product
sedimentary