Chert (with Quartz veins)
Microcrystalline Quartz (SiO2)
sedimentary
Category
Sedimentary Or Igneous (Secondary Formation)
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Mica-rich schist (likely quartz-mica schist)
Quartz–mica schist, commonly containing muscovite and/or biotite with quartz and feldspar
metamorphic
Chert (Jasper/Pink Chert)
Silicon Dioxide (SiO2)
sedimentary
Milky Quartz with Iron Staining
Silicon Dioxide (SiO2)
mineral
Orange Calcite
Calcium Carbonate (CaCO3)
mineral
Yellow Chalcedony (Agate Pebble)
Silicon Dioxide (SiO2)
mineral
Limonite (Iron-rich Siltstone / Sandstone base)
Hydrous ferric oxide mixture (FeO(OH)·nH2O)
sedimentary
Tumbled Agate
Silicon Dioxide (SiO2)
mineral
Amazonite
Amazonite (KAlSi3O8 – a variety of Microcline, a Potassium Feldspar)
mineral
Quartz (Milky/Common Quartz)
Silicon Dioxide (SiO2)
mineral
Banded Chert (Jasper)
Silicon Dioxide (SiO2)
sedimentary
Agate (specifically, a slice of a Blue Lace or Chalcedony Agate nodule)
Silicon Dioxide (SiO2) - Cryptocrystalline Quartz
mineral
Orange Calcite
Calcium Carbonate (CaCO3)
mineral
Hematite
Iron Oxide (Fe2O3)
mineral
Likely mica schist
Mica-rich schist, probably muscovite–biotite schist
metamorphic
Polished garnet-bearing metamorphic rock
Likely garnet mica schist or garnet-bearing gneiss; garnet is commonly almandine, Fe₃Al₂(SiO₄)₃
metamorphic
Kaolinite (Chalky Clay)
Kaolinite (Al2Si2O5(OH)4)
sedimentary
Garnet-bearing schist or gneiss
Garnet-mica schist/gneiss; chiefly quartz, feldspar, mica, and almandine–pyrope garnet
metamorphic
Quartz
Silicon Dioxide (SiO2)
mineral
Pink Granite
Phaneritic Felsic Igneous Rock (high K-feldspar)
igneous
Gneiss
Gneiss (Metamorphic Rock)
metamorphic
Vesicular Basalt
Basalt (Mafic Extrusive Volcanic Rock)
igneous
Unidentified small rock fragment
Likely quartz-rich material; exact identification is indeterminate from the image
mineral
Unidentified gray-brown stone
Likely fine-grained quartz–feldspar rock; exact identification is not possible from this close, blurred image
mineral
Feldspar (specifically Orthoclase or Plagioclase)
Potassium Aluminum Silicate (KAlSi3O8) or Sodium/Calcium Aluminum Silicate
mineral
Unidentifiable Rock Fragment
Uncertain
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
mineral
Banded Chert / Agate
Silicon Dioxide (SiO2)
sedimentary
Weathered Sedimentary Rock with Liesegang Rings
Sandstone or Siltstone with Iron Oxide Banding
sedimentary
Quartz with Iron Oxide Inclusions
SiO2
mineral
Mixed mineral and rock collection
Predominantly quartz varieties, including amethyst, plus likely calcite, feldspar, mica, and miscellaneous polished stones
mineral
Milky Quartz
SiO2 (Silicon Dioxide)
mineral
Rhodonite
Manganese Silicate (Mn,Fe,Mg,Ca)SiO3
mineral
Quartz
Silicon Dioxide (SiO2)
Mineral
Fluorite
Calcium fluoride (CaF2)
mineral
Geode with Quartz Crystals
SiO2 (Silicon Dioxide) in a geode formation
Sedimentary/Igneous (depending on host rock)
Native Sulfur
Sulfur (S8)
mineral
Satin Spar (Selenite)
Gypsum (CaSO4·2H2O)
mineral
Banded metamorphic rock, likely schist or gneiss
Foliated quartz–feldspar–mica rock; exact mineral identification requires sampling
metamorphic
Red Jasper
Silicon Dioxide (SiO2) with Iron inclusions
sedimentary
Quartz Geode
Silicon Dioxide (SiO2)
mineral
Quartz (Iron-stained)
Silicon Dioxide (SiO2)
mineral