Ferruginous Sandstone Concretion (Ironstone Phosphorite)
Ferruginous Sandstone (variable Fe-oxide/hydroxide composition)
sedimentary
Category
Mineral, Sediment
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Muscovite Mica
Muscovite: KAl2(AlSi3O10)(OH)2
mineral
Weathered iron-rich metamorphic rock, likely schist or quartzite
Provisional identification: ferruginous quartzite or mica schist; composition likely quartz (SiO₂), iron oxides/hydroxides, and mica or clay minerals
metamorphic
Banded calcite (travertine/cave calcite)
Calcite, CaCO₃; likely banded carbonate travertine or flowstone
mineral
Likely weathered mica schist fragment
Mica schist, chiefly muscovite/biotite mica with quartz and feldspar
metamorphic
Glauconite (Greensand)
(K, Na)(Fe3⁰, Al, Mg)₂(Si, Al)₄O₁₀(OH)₂
sedimentary
Calamites (Fossilized Horsetail)
Calamites suckowii (Family: Calamitaceae)
sedimentary
Ammonite Fossil
Ammonoidea
fossil
Orbicular jasper (picture jasper)
Silicified volcanic or sedimentary rock; chiefly microcrystalline quartz (SiO₂) with iron-oxide pigments
sedimentary
Polished brecciated jasper
Jasper, microcrystalline quartz (SiO₂), with iron-oxide and other mineral inclusions
gemstone
Jasper and Mixed River Pebbles
Microcrystalline Quartz (Chalcedony / Jasper)
sedimentary
Red jasper (likely iron-rich chert)
Microcrystalline quartz (SiO₂), colored by hematite/goethite; possibly brecciated jasper
sedimentary
Fossil Shark Tooth
Chondrichthyes (Class)
fossil
Fossil Crab
Decapoda (likely Avitelmessus or Raninidae family)
sedimentary
Jasper with Epidote
Silicon Dioxide (SiO2) with Calcium Aluminum Iron Silicate Hydrate
sedimentary
Petrified Wood
Silicified wood (Quartz / Chalcedony replacement of organic cellulose)
fossil
Wishing Stone (Quartz-veined Siltstone or Graywacke)
Hydrothermal Quartz vein in matrix of SiO2 (Quartz) and Al2O3 (Clay minerals)
sedimentary
Almandine Garnet
Almandine (Fe3Al2(SiO4)3)
mineral
Red Hematite (Banded Iron Formation)
Hematite (Fe2O3)
mineral
Petrified Wood
Silicified Wood (primarily SiO2 - Silicon Dioxide)
mineral
Shark Tooth Fossil
Lamniformes (Shark tooth fossil composed of Fluorapatite)
fossil
Amber
Succinite (C10H16O)
mineraloid
Shark Tooth Fossil
Carcharhiniformes or Lamniformes (order level fossil)
fossil
Jasper (Mookaite variety likely)
Silicon Dioxide (SiO2) with iron oxide inclusions
sedimentary
Petrified Wood
Silicified Wood (primarily SiO2)
metamorphic
Fossilized Shark Tooth (Partial) or Coprolite
Elasmobranchii (fossil) or Coprolite (trace fossil)
fossil
Quartz (River Pebble)
Silicon Dioxide (SiO2)
mineral
Chiastolite
Andalusite (Al2SiO5) with carbonaceous inclusions
metamorphic
Fossilized Bivalve Shell
Class Bivalvia (fossilized)
fossil
Enrolled Trilobite Fossil
Phylum Arthropoda, Class Trilobita (likely Calymene or Flexicalymene)
fossil
Petrified Wood
Silicified Wood (primarily SiO2)
fossil
Petrified Wood
Silicified Wood (SiO2)
fossil
Blue Quartz (Blue Aventurine)
Silicon Dioxide (SiO2) with inclusions of Dumortierite or Crocidolite
metamorphic
Petrified Wood
Silicified Wood (SiO2)
mineral
Hematite (Tumbled)
Iron(III) oxide (Fe2O3)
mineral
Muscovite Mica
KAl2(AlSi3O10)(F,OH)2
mineral
Fossilized Tabulate Coral (Honeycomb Coral)
Favosites (Order: Tabulata)
sedimentary
Chert Nodules
Chert (Silicon Dioxide, SiO2)
sedimentary
Petrified Wood
Silicified Wood (primarily SiO2)
sedimentary
Green Aventurine
Aventurine Quartz (SiO2 containing Fuchsite)
metamorphic
Fossilized Echinoid / Sea Urchin Internal Mold
Echinoidea internal cast (steinkern)
fossil
Iron-rich quartzite or silicified ironstone
Quartz (SiO₂) with iron oxides/hydroxides, likely limonite/goethite and possibly hematite
metamorphic