Aquamarine
Beryl (Be3Al2Si6O18 with Fe2+ impurities)
mineral
Category
Sedimentary (Secondary Mineral) Within Igneous
Browse sedimentary (secondary mineral) within igneous specimens identified by the Rock Identifier community.
Banded Chert (Jasper)
Silicon Dioxide (SiO2)
sedimentary
Limonite (Iron Ore Congcretion)
Limonite (a mixture of hydrated iron(III) oxide-hydroxides, FeO(OH)·nH2O)
mineral
Botryoidal Hematite (included in Quartz/Limonite matrix)
Fe2O3 (Hematite) on Quartz (SiO2) / Limonite
mineral
Gneiss (with Quartzite and Mica)
Gneiss
metamorphic
Prasiolite
Silicon Dioxide (SiO2) with iron impurities
mineral
Limonite
Limonite (FeOO·nH2O)
mineral
Amygdaloidal Rhyolite (often called Lake Superior Agate relative)
Rhyolite with Calcite/Quartz amygdules (SiO2 and secondary minerals)
igneous
Gneiss
Gneiss (High-grade regional metamorphic rock)
metamorphic
Gneiss
Gneiss (High-grade regional metamorphic rock)
metamorphic
Limestone with Calcite Crystals
Calcium Carbonate (CaCO3)
sedimentary
Ferruginous Quartz
Silicon Dioxide (SiO2) with Iron Oxide (Fe2O3) inclusions
mineral
Chalcedony on Matrix
Silicon Dioxide (SiO2)
mineral
Iron-stained Quartz
Silicon Dioxide with Iron Oxide (SiO2 with Limonite/Hematite impurities)
mineral
Chlorastrolite (Isle Royale Greenstone)
Chlorastrolite (Pumpellyite-(Mg,Fe2+): Ca2MgAl2(Si2O7)(SiO4)(OH)2∙H2O)
mineral
Limonite with Hematite
Limonite (FeO(OH)·nH2O) and Hematite (Fe2O3)
mineral
Gneiss (specifically Micaceous Gneiss)
Gneiss (High-grade Regional Metamorphic Rock)
metamorphic
Chert (Jasper/Agate variety)
Microcrystalline quartz (SiO2)
sedimentary
Dalmatian Stone
Dalmatian Jasper (Aplitic Rock)
igneous
Quartz Vein with Iron Staining
Silicon Dioxide (SiO2) with limonite/hematite staining
mineral
Quartz / Iron-Stained Quartz
Silicon Dioxide (SiO2) with iron oxide inclusions/staining
mineral
Copper-bearing Quartz (likely Malachite on Quartz matrix)
Cu2CO3(OH)2 (Malachite) on SiO2 (Quartz)
mineral
Satin Spar (Gypsum)
Hydrous Calcium Sulfate (CaSO4·2H2O)
mineral
Diamond
Diamond (pure carbon, C)
mineral
Sandstone with Secondary Mineral Encrustation
Arenite with Silica/Calcite deposits (SiO2 or CaCO3)
sedimentary
Limonite (Iron Ore)
Limonite (FeO(OH)·nH2O)
mineral
Limonite (Iron Ore)
FeO(OH)·nH2O (Hydrous ferric oxide)
mineral
Quartz Geode (partially opened)
Silicon Dioxide (SiO2) with iron staining
mineral
Biotite Gneiss
Gneiss (complex mixture including Biotite K(Mg,Fe)3AlSi3O10(F,OH)2 and Quartz/Feldspar)
metamorphic
Copper-bearing Quartz (with Malachite and Iron Oxides)
Quartz (SiO2) with Malachite (Cu2CO3(OH)2) and Hematite/Limonite (Fe2O3)
Mineral Specimen
Gneiss
Gneiss
metamorphic
Amethyst with Marcasite accents
Amethyst (Silicon Dioxide SiO2) and Marcasite (Iron Sulfide FeS2)
mineral
Chalcedony (Agate)
Cryptocrystalline Quartz (SiO2)
mineral
Quartz (Milky or Druzy Quartz)
Silicon Dioxide (SiO2)
mineral
Agate
Silicon Dioxide (SiO2) - variety of Chalcedony
mineral
Amygdaloidal Basalt
Amygdaloidal Basalt (Mafic Volcanic Rock)
igneous
Amygdaloidal Basalt
Basalt with secondary mineral infilling (commonly Zeolite, Calcite, or Quartz)
igneous
Agate Geode
Chalcedony (cryptocrystalline SiO2)
mineral
Quartz Geode Fragment
Silicon Dioxide (SiO2)
mineral
Sedimentary rock with quartz veining
Laminated siltstone or mudstone with hydrothermal quartz veins
sedimentary
Quartz (Sea Glass or River-worn Pebble style)
Silicon Dioxide (SiO2)
mineral
Blue Sapphire (faceted in jewelry)
Corundum (Al2O3)
mineral