Granite
Phaneritic Igneous Rock (composed primarily of Quartz, Alkali Feldspar, and Plagioclase)
igneous
Category
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Limonite/Goethite nodule
Goethite (FeO(OH)) with Hydrated Iron Oxides
mineral
Concretion or Geode (unbroken)
Varied (depending on mineral composition and cementing agent). For quartz-lined geodes, the scientific name of the dominant mineral would be Quartz (SiO2). For calcite-lined geodes, Calcite (CaCO3). Concretions are often composed of cryptocrystalline quartz (chert), calcite, or iron oxides.
Sedimentary rock (specifically a concretion or possibly a geode)
Granite / Gneiss Complex
Felsic Plutonic Rock (Granite) or High-grade Metamorphic Rock (Gneiss)
igneous/metamorphic
River Jasper
Silicon Dioxide (SiO2) with impurities
sedimentary
Sandstone
Arenite (SiO2 with various cementation agents)
sedimentary
Banded Slate (Sedimentary Pebble)
Slate (Metamorphosed Shale or Mudstone)
metamorphic
Petrified Wood
Silicified Wood (SiO2)
sedimentary
Quartzite
Quartzite (primarily SiO2)
metamorphic
Hag Stone
Perforated Sedimentary Rock (typically Limestone or Sandstone)
sedimentary
Gossan with Copper Carbonate (Chrysocolla/Malachite)
Ferruginous Oxide (Gossan) with Cu2CO3(OH)2 (Malachite) or (Cu,Al)2H2Si2O5(OH)4 (Chrysocolla)
Mineral/Sedimentary Interface
Granite
Granite (Mainly Quartz SiO2 and Feldspar KAlSi3O8)
igneous
Quartzite River Rock
Quartzite (primarily SiO2)
metamorphic
Granitic Pegmatite
Coarse-grained Igneous Rock (Granitic composition: KAlSi3O8, SiO2)
igneous
Fluorite
Calcium Fluoride (CaF2)
mineral
Diamond
Native Carbon (C)
mineral
Shale or Argillite
Shale (fine-grained clastic sedimentary rock) or Argillite (low-grade metamorphic rock derived from shale)
Sedimentary or Metamorphic (low grade)
Schist
Mica Schist
metamorphic
Pink Halite (Himalayan Salt)
Halite (Sodium Chloride, NaCl)
sedimentary
Banded Gneiss
Gneiss (High-grade Metamorphic Rock)
metamorphic
Diorite (Salt and Pepper Rock)
Diorite
igneous
Diorite
Intrusive Igneous Diorite
igneous
Gneiss
High-grade metamorphic rock (Gneiss)
metamorphic
Granite Pebble
Intrusive Felsic Igneous Rock (Granite)
igneous
Granite
Granite (Phaneritic intrusive igneous rock)
igneous
Granite Gneiss
Gneiss (High-grade metamorphic rock)
metamorphic
Granite
Intrusive igneous felsic rock
igneous
Manganese Dendrite on Siltstone
Manganese Oxide (pyrolusite or psilomelane) Dendrites
mineral/sedimentary
Citrine
Silicon Dioxide (SiO2)
Mineral
Quartz (likely Jasper or Chert variety)
Quartz (SiO₂)
Mineral
Jasper-Agate Breccia
Silicon Dioxide (SiO2) with iron oxide inclusions
sedimentary
Geode (Unopened)
Silica Concretion / Geode (Formula: SiO2 for quartz internal contents)
sedimentary
Quartz (likely a macrocrystalline variety like milky quartz or smoky quartz, given the appearance in the image)
Quartz (SiO₂ - Silicon Dioxide)
Mineral
Amygdaloidal Basalt
Amygdaloidal Basalt (Mafic volcanic rock)
igneous
Citrine
Silicon Dioxide (SiO2)
mineral
Moss Agate
Silicon Dioxide (SiO2) with mineral inclusions of hornblende or chlorite
Mineral (variety of Chalcedony)
Granite Pebble
Granitoid (Felsic Plutonic Rock)
igneous
Mica Schist
Mica Schist (primarily Muscovite or Biotite-rich sequence)
metamorphic
Granite
Phaneritic plutonic rock (SiO2-rich)
igneous
Synthetic Sapphire and Ion-X Glass
Single-crystal Alumina (Al2O3) and Ion-strengthened Aluminosilicate Glass
mineral
Schist (Diamond Drill Core)
Mica Schist
metamorphic
Milky Quartz
Silicon Dioxide (SiO2)
mineral