Limonite (also known as Yellow Ochre or Brown Hematite)
Limonite (Hydrated iron oxide-hydroxide, FeO(OH)·nH2O)
Mineral
Category
Organic (Pseudo Geological)
Browse organic (pseudo geological) specimens identified by the Rock Identifier community.
Tiger's Eye
Silicon dioxide (SiO2) with fibrous inclusions of crocidolite (riebeckite)
Mineral
Muscovite Mica
Muscovite (Potassium Aluminum Silicate Hydroxide Fluoride), KAl2(AlSi3O10)(OH,F)2
mineral
Azurite and Malachite on Matrix
Azurite: Cu3(CO3)2(OH)2; Malachite: Cu2CO3(OH)2
mineral
Tiger's Eye (commonly referred to as Blue/Gold Tiger's Eye)
Tiger's Eye is a variety of Chalcedony (cryptocrystalline quartz), SiO2, exhibiting chatoyancy. The blue variety is often called Hawk's Eye.
Metamorphic Rock (formed from a fibrous crocidolite asbestos)
Goethite
Goethite (α-FeO(OH))
Mineral
Limonite
Hydrous Iron Oxide (often Goethite FeO(OH), Lepidocrocite γ-FeO(OH), and other amorphous iron oxyhydroxides)
Mineral
Sandstone with trace fossil
Sandstone, possibly with Skolithos or similar trace fossil
sedimentary
Conglomerate
Conglomerate (a clastic sedimentary rock)
Sedimentary
Goldstone (with Tiger's Eye and Quartz)
Aventurine glass (Synthetic SiO2 with Cu inclusions)
mineral
Biotite Mica
K(Mg,Fe)3AlSi3O10(OH)2
Mineral in a matrix (likely quartz or feldspar)
Tiger's Eye
Silicon dioxide (SiO2) with fibrous inclusions of crocidolite (riebeckite) that have been altered to limonite and then replaced by quartz
Mineral
Blue Tiger's Eye
Crocidolite in Quartz (altered)
Mineral
Tiger's Eye
Tiger's Eye (a variety of Chalcedony, which is cryptocrystalline quartz). Chemical Formula: SiO2 with inclusions of crocidolite fibers.
Mineral
Tiger's Eye
Tiger's Eye (a variety of Quartz, SiO₂)
Mineral (specifically a gemstone variety)
Hawk's Eye (Blue Tiger's Eye)
Quartz (fibrous crocidolite variety)
Mineral
Blue Tiger's Eye
Crocidolite (fibrous riebeckite) silicified to Quartz (SiO2)
Mineral
Blue Tiger's Eye
Riebeckite (crocidolite variety)
Mineral
Tiger's Eye
Tiger's Eye (a variety of Chalcedony, which is a microcrystalline quartz with fibrous inclusions of oxidized crocidolite)
Mineral
Mica Group Minerals
There isn't a single scientific name as 'Mica' refers to a group of phyllosilicate minerals. Common scientific names include Muscovite (KAl₂ (AlSi₃O₁₀)(OH)₂), Biotite (K(Mg,Fe)₃AlSi₃O₁₀(OH)₂), Phlogopite (KMg₃AlSi₃O₁₀(OH)₂), and Lepidolite (K(Li,Al)₃(Al,Si,Rb)₄O₁₀(F,OH)₂).
Mineral
Quartz (Milky Quartz)
Silicon Dioxide (SiO2)
mineral
Unakite
Epidotized Granite
metamorphic
Chert / Jasper
Silicon Dioxide (SiO2)
sedimentary
Granite
Granite (High-silica plutonic rock)
igneous
Calcite
Calcium Carbonate (CaCO3)
mineral
Chert Pebble
Silicon dioxide (SiO2)
sedimentary
Chert / Flint
Silicon dioxide (SiO2)
sedimentary
Quartzite
Quartzite (primarily SiO2)
metamorphic
Yellow Calcite
Calcium Carbonate (CaCO3)
mineral
Rough Green Calcite
Calcite (Calcium Carbonate, CaCO3)
mineral
Granite
Granite (Mainly Quartz, Alkali Feldspar, and Plagioclase)
igneous
Chert (Jasper variation)
Silicon dioxide (SiO2)
sedimentary
Chert (potentially Flint or Mudstone)
Microcrystalline Quartz (SiO2)
sedimentary
Schist
Mica Schist (Medium-grade metamorphic rock)
metamorphic
Yellow Chert or Jasper
Silicon Dioxide (SiO2)
sedimentary
Chert (Nodular flint)
Microcrystalline or cryptocrystalline Quartz (SiO2)
sedimentary
Orange Calcite
Calcium Carbonate (CaCO3)
mineral
Quartz / Chert
Silicon Dioxide (SiO2)
Mineral / Sedimentary
Schist (Biotite Schist)
Biotite-bearing Schist (K(Mg,Fe)3AlSi3O10(F,OH)2)
metamorphic
Granite
Granite (Phaneritic Igneous Rock)
igneous
Chert (specifically Gray Chert)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
sedimentary
Green Aventurine
Silicon Dioxide with Fuchsite inclusions (SiO2 + K(Al,Cr)2AlSi3O10(OH)2)
mineral