Chert (Nodule)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
sedimentary
Category
Anthropogenic Material (Man Made Rock)
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Green Aventurine
Quartz (SiO2) with Fuchsite inclusions
Mineral
Chalk
CaCO3 (primarily Calcium Carbonate), biogenic sedimentary rock
Sedimentary
Mica Schist
Mica Schist (principally Biotite/Muscovite, Quartz, and Feldspar)
metamorphic
Quartz with Mafic/Chlorite Veins
Silicon Dioxide (SiO2) with Chlorite/Epidote cross-veining
metamorphic
Tumbled iron-rich stone, likely hematite-bearing jasper
Jasper (microcrystalline quartz, SiO₂) with iron oxides, chiefly hematite/goethite
mineral
Malaysian 50 Sen Coin
Coinage (specific alloy unknown without metallurgical analysis, but typically brass or bronze for this denomination and era)
Man-made object (coin)
Fossilized Bored Limestone
Limestone with Ichnofossils (Gastrochaenolites or Entobia)
sedimentary
Desert Rose (also known as Sand Rose)
Gypsum (CaSO4·2H2O) or Barite (BaSO4) with sand inclusions
mineral
Chert (River Siltstone/Quartzite type)
Microcrystalline Quartz (SiO2)
sedimentary
Crinoid Fossil Stem Segment
Class Crinoidea (Echinodermata)
sedimentary
Blue-beaded gemstone jewelry, likely lapis lazuli or dyed blue agate
Uncertain from the image; possible lazurite-bearing lapis lazuli (Na₃Ca(Si₃Al₃)O₁₂S) or blue chalcedony (SiO₂)
gemstone
Sandstone
Sandstone (clastic sedimentary rock, predominantly SiO2)
sedimentary
Sandstone with Lichen and Iron Oxide Staining
Quartz Arenite / Sandstone
sedimentary
Granite
Phaneritic Plutonic Felsic Rock (SiO2, KAlSi3O8, NaAlSi3O8, CaAl2Si2O8)
igneous
Granite
Granite (Silicic Intrusive Igneous Rock)
Igneous
Amethyst (Tumbled Cabinet Stone)
Silicon Dioxide (SiO2) with iron impurities
mineral
Grey Granite
Phaneritic Felsic Intrusive Igneous Rock
igneous
Petrified Wood
Silicified Wood (SiO2)
sedimentary
Quartz
Silicon dioxide (SiO₂)
Mineral
Natural or Cultured Pearl
Calcium Carbonate (Aragonite and Conchiolin), CaCO3
Mineral (Organic)
Jasper
Silicon Dioxide (SiO2)
sedimentary
Quartzite
Silica (SiO2) quartzite
metamorphic
Chert (and Flint)
Silicon Dioxide (SiO2)
sedimentary
Chert (specifically White Chert or Novaculite)
Silicon Dioxide (SiO₂)
sedimentary
Carved quartz skull, likely smoky quartz or gray chalcedony
Silicon dioxide (SiO₂), quartz or microcrystalline quartz
gemstone
Note: No specimen visible
N/A
Pink Granite (Alkali-feldspar Granite)
Felsic intrusive igneous rock (composition: KAlSi3O8, SiO2, NaAlSi3O8)
igneous
Polished white chalcedony or milky quartz pebble
Chalcedony, microcrystalline quartz (SiO₂), possibly with iron-oxide staining or a minor mineral inclusion
mineral
Pearls (likely freshwater cultured pearls)
Pearl: nacre, primarily aragonite (CaCO₃) with conchiolin
gemstone
Vesicular volcanic rock, likely weathered pumice or scoria
Pumice/scoria; predominantly volcanic glass and feldspar, with possible iron oxides
igneous
Carved quartz (likely rose quartz and green aventurine/quartz)
Quartz, silicon dioxide (SiO₂); green material may be aventurine quartz or serpentine
gemstone
Breccia
Breccia
sedimentary
Chert / Flint
Chert (varieties include Flint)
Sedimentary
Quartz Sandstone Pebble
Sandstone (SiO2 dominated)
sedimentary
Polymictic breccia, possibly volcanic breccia
Polymictic clastic breccia; likely a matrix-supported breccia containing lithic fragments, quartz, feldspar, and dark mafic minerals
sedimentary
Iron Slag
Ferrous Slag (Industrial Byproduct)
mineraloid (anthropogenic byproduct)
Diorite
Diorite
igneous
Diamond
Carbon (C)
gemstone
Quartzite
Quartzite (SiO2)
metamorphic
Diorite
Diorite (Intermediate intrusive igneous rock)
igneous
Granite
Granite (Phaneritic Quartz-Feldspar intrusive rock)
Igneous