Iolite (Cordierite)
Cordierite (Magnesium Aluminum Silicate), Mg2Al4Si5O18
Mineral
Category
Metamorphic Or Sedimentary
Browse metamorphic or sedimentary specimens identified by the Rock Identifier community.
Learn about Metamorphic Or Sedimentary in the encyclopedia
View all →
Garnet Schist
Mica Schist with Almandine (Fe3Al2(SiO4)3)
metamorphic
Mixed collection of Quartz varieties, Chalcedony, and metamorphic pebbles
Mixed gemstones (primarily Silicon Dioxide - SiO2)
mineral
Chert (or potentially massive Quartz/Quartzite)
SiO2 (Silicon Dioxide)
sedimentary (if chert) / metamorphic (if quartzite)
Green Aventurine
Silicon Dioxide (Quartz) with Fuchsite inclusions (K(Al,Cr)2(AlSi3O10)(OH)2)
metamorphic
Mica (likely Muscovite)
Muscovite / KAl2(AlSi3O10)(OH)2
mineral
Quartz Vein in Metamorphic Rock
Quartzite or Schist host with Quartz (SiO2) intrusion
metamorphic
Yellow Sapphire or Citrine
Al2O3 (Corundum) or SiO2 (Quartz)
mineral
Green Tourmaline
Elbaite (part of Tourmaline group), Na(Li1.5Al1.5)Al6Si6O18(BO3)3(OH)4
mineral
Apatite
Apatite Group (e.g., Fluorapatite Ca5(PO4)3F, Chlorapatite Ca5(PO4)3Cl, Hydroxylapatite Ca5(PO4)3(OH))
mineral
Rock Crystal Quartz
Quartz (SiO₂)
Mineral
Hematite
Hematite (Fe2O3)
mineral
Black Tourmaline
Schorl (Na(Fe²⁺)₃Al₆(BO₃)₃Si₆O₁₈(OH)₄)
Mineral
Osumilite in Granite Matrix
(K,Na)(Fe,Mg)2(Al,Fe)3(Si,Al)12O30
mineral
Ruby Fuchsite / Ruby in Fuchsite
Ruby (Al2O3 variety corundum) and Fuchsite (K(Al,Cr)2AlSi3O10(OH)2 - a chromium-rich variety of muscovite mica) in Quartz matrix
Mineral
Red Garnet
Pyrope or Almandine (X3Y2(SiO4)3)
mineral
Red Jasper
Jasper (Silicon Dioxide with Iron inclusions - SiO2)
Sedimentary/Metamorphic
Jasper (Iron-rich Chalcedony)
Jasper (Microcrystalline Silicon Dioxide, SiO2 plus iron oxide impurities)
Sedimentary / Metamorphic
Quartzite with Mafic Intrusion (Gneiss/Schist Contact)
Metamorphic Quartzite (SiO2) with Amphibole/Biotite Schist
metamorphic
Muscovite Mica
Muscovite (Potassium Mica) KAl2(AlSi3O10)(OH)2
Mineral
Garnet
Almandine Garnet (Fe3Al2(SiO4)3)
mineral
Rhodonite
Manganese Silicate (Mn,Fe,Mg,Ca)SiO3
mineral
Green Aventurine
Aventurine Quartz (SiO2 with Fuchsite inclusions)
mineral
Rhodonite
Rhodonite (Mn,Fe,Mg,Ca)SiO3
mineral
Fossiliferous Shale or Slate with Plant Fossils
Fossil-bearing argillaceous rock
Sedimentary/Metamorphic
Quartz on Chlorite Schist
Chlorite Schist (Mg,Fe)3(Si,Al)4O10(OH)2 with Quartz (SiO2)
metamorphic
Green Aventurine
Silicon Dioxide (Quartz with Fuchsite inclusions) - SiO2
mineral
Tiger's Eye
Pseudomorph of Quartz after Crocidolite (SiO2)
metamorphic
Calcite
Calcite (CaCO3)
Mineral
Magnetite
Magnetite (Fe3O4)
Mineral
Lapis Lazuli
Lapis Lazuli (a rock composed primarily of Lazurite)
Metamorphic rock
Quartz (various varieties)
SiO₂ (Silicon Dioxide)
Mineral
Calcite (commonly referred to as Orange Calcite or Honey Calcite given its color)
Calcite
Mineral
Tiger's Eye and Carnelian Quartz
Silicon Dioxide (SiO2)
metamorphic and mineral
Almandine Garnet
Almandine - Fe3Al2(SiO4)3
mineral
Lapis Lazuli
Lapis Lazuli (Na,Ca)8(AlSiO4)6(S,SO4,Cl)1-2
metamorphic
Quartz Pebble
Silicon Dioxide (SiO2)
Mineral / Sedimentary occurrence
Almandine Garnet
Almandine, Fe3Al2(SiO4)3
mineral
Aventurine
Silicon Dioxide (SiO2) with Fuchsite inclusions
metamorphic
Green Aventurine
Silicon dioxide (SiO2) with inclusions of Fuchsite mica
metamorphic
Rhodonite
Manganese Silicate (Mn, Fe, Mg, Ca)SiO3
mineral
Quartz Vein in Host Rock
Silicon Dioxide (SiO2)
mineral