Basalt Pebble
Mafic Igneous Rock (Basalt)
igneous
Category
Mineral, Part Of A Rock
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Basalt
Basalt (Mafic volcanic rock)
igneous
Basalt River Stone
Basalt
igneous
Crinoid Stem Fossil
Crinoid columnal (Class Crinoidea)
sedimentary
Jasper
Silicon dioxide (SiO2)
sedimentary
Granite
Granite (composed of Quartz, Feldspar, and Mica)
igneous
Sandstone
Arenite (composed primarily of SiO2)
sedimentary
Engineered Quartz (Quartzite look-alike)
Silicon Dioxide (SiO2) composite
mineral-based composite
Kaibab Limestone
Calcitic limestone, predominantly calcium carbonate (CaCO₃)
sedimentary
Biotite / Black Mica
Biotite K(Mg,Fe)3AlSi3O10(F,OH)2
mineral
Ptygmatic Migmatite
Migmatite (consisting of Neosome and Paleosome fractions)
metamorphic
Ferruginous Quartz (Iron-stained Quartz)
Silicon Dioxide with Iron Oxide (SiO2 + Fe2O3)
mineral
Polished garnet bead (likely almandine)
Almandine garnet, Fe₃Al₂(SiO₄)₃ (tentative visual identification)
gemstone
Rugose Coral (Horn Coral Fossil)
Order Rugosa (fossilized in limestone/chert)
sedimentary
Greywhacke (River Pebble)
Graywacke (immature sandstone)
sedimentary
Weathered granite fragment
Granite, chiefly quartz, feldspar, and mica
igneous
Conglomerate (River Rock Aggregate)
Conglomerate (Lithic-clast conglomerate)
sedimentary
Echinoid Fossil / Fossilized Sea Urchin
Echinoidea
fossil
Rounded basalt pebble
Basalt, a fine-grained mafic volcanic rock composed mainly of plagioclase feldspar and pyroxene, commonly with olivine and magnetite
igneous
Red Jasper
Silicon dioxide (SiO2) with iron oxide impurities
mineral
Basalt
Basalt (Aphanitic Mafic Volcanic Rock)
igneous
Lapis Lazuli
Lapis Lazuli (Metamorphic rock containing lazurite (Na,Ca)8(AlSiO4)6(S,Cl,SO4,OH)2, calcite, and pyrite)
metamorphic
Quartz-rich rock, possibly quartzite
Quartzite (dominantly quartz, SiO₂); identification is provisional from the photo
metamorphic
Iron-rich sandstone or weathered laterite fragment
Quartz-rich sandstone, possibly ferruginous sandstone (SiO₂ with iron oxides such as hematite/goethite)
sedimentary
Weathered quartz-rich rock fragment
Likely granitic or pegmatitic fragment; chiefly quartz (SiO₂) with feldspar and iron-oxide staining
igneous
Quartz Druzy on Matrix
Silicon Dioxide (SiO2)
mineral
Small brown jasper or chert fragment
Microcrystalline quartz (SiO₂), likely iron-stained jasper/chert
sedimentary
Banded quartzite pebble
Quartzite, predominantly crystalline quartz (SiO₂), with darker accessory minerals
metamorphic
White quartz pebble
Quartz (silicon dioxide, SiO₂), likely milky quartz
mineral
Quartz Pebble
Silicon Dioxide (SiO2)
mineral
River Pebble (Greywacke or Basaltic)
Massive Greywacke or Basaltic Andesite
sedimentary or igneous
Crushed Stone / Greywacke
Greywacke (Indurated Sandstone)
sedimentary
Quartz (specifically Milky Quartz Pebble)
Silicon Dioxide (SiO2)
mineral
Quartzite (or Milky Quartz pebble)
Quartzite (primarily Silicon Dioxide, SiO2)
metamorphic
Quartzite pebble
Quartzite (primarily SiO2)
metamorphic
Quartz Pebble
Silicon Dioxide (SiO2)
mineral
Calcite
Calcium Carbonate (CaCO3)
mineral
Dolerite (Diabase)
Dolerite / Diabase
igneous
Granite (Pink/Red Granite)
Phaneritic Igneous Rock (primarily SiO2, KAlSi3O8, NaAlSi3O8)
igneous
Polished fossil ammonite slice
Ammonoidea (commonly polished juvenile ammonite or nautiloid-like cephalopod fossil)
fossil
Chert / Quartz Pebble
Silicon Dioxide (SiO2) - Microcrystalline Quartz
sedimentary
Quartz (Clear/White)
Silicon Dioxide (SiO2)
mineral