Prehnite
Prehnite (Ca2Al(AlSi3O10)(OH)2)
mineral
Category
Metamorphic (Low Grade)
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Prehnite
Prehnite (Ca2Al(AlSi3O10)(OH)2)
mineral
Serpentine
Serpentinite (composed mainly of Group Minerals Antigorite, Chrysotile, and Lizardite; Mg3Si2O5(OH)4)
metamorphic
Greenstone
Metabasalt / Greenschist
metamorphic
Greenstone
Protolith of basalt, diabase, or gabbro; often contains minerals like chlorite, actinolite, and epidote
metamorphic
Green Slate (Greenstone)
Foliated Metamorphic Rock (rich in Chlorite/Epidote)
metamorphic
Greenschist
Greenschist (Chlorite Schist)
metamorphic
Likely blue-gray slate fragment
Slate, a fine-grained metamorphic rock composed chiefly of mica-group minerals and quartz
metamorphic
Greenstone (likely chlorite-rich metamorphic rock)
Greenschist; commonly composed of chlorite, actinolite, and epidote, with possible albite
metamorphic
Dark gray metamorphic rock, likely slate or phyllite
Fine-grained foliated rock composed mainly of mica, chlorite, and quartz; exact identification requires testing
metamorphic
River Cobble (likely Metasedimentary or Basalt)
Metamorphosed Siltstone or Altered Fine-grained Igneous Rock
metamorphic
Epidote (Greenstone)
Epidote (Ca2(Al2,Fe)(SiO4)(Si2O7)O(OH))
metamorphic
Riverstone (likely Gray Slate or Siltstone)
Metamorphosed fine-grained sedimentary rock (Argillite/Slate)
metamorphic
Foliated metamorphic rock, likely slate or phyllite
Slate–phyllite; primarily quartz, mica, and clay-derived minerals
metamorphic
Greenstone
Metabasalts and metavolcanics
metamorphic
Basalt with Epidote (Greenstone)
Epidote-bearing Metabasalt
metamorphic
Nephrite Jade
Nephrite (Silicate mineral: Ca2(Mg, Fe)5Si8O22(OH)2)
metamorphic
Greenstone
Chlorite schist or metabasalt depending on specific composition
Metamorphic
Slate
Metamorphic pelitic rock
metamorphic
Banded Slate
Slate (Metamorphosed Siltstone/Mudstone)
metamorphic
Greenstone (likely chlorite-rich metamorphic rock)
Chlorite-rich greenschist; commonly composed of chlorite, actinolite, and epidote
metamorphic
Chlorite (Small Flakes/Sand)
Chlorite Group (Magnesium Iron Aluminum Silicate Hydroxide - (Mg,Fe)3(Si,Al)4O10(OH)2·(Mg,Fe)3(OH)6)
mineral
Jade
Nephrite (Ca2(Mg,Fe)5Si8O22(OH)2) or Jadeite (NaAlSi2O6)
mineral
Jade
Nephrite (Ca2(Mg,Fe)5Si8O22(OH)2) or Jadeite (NaAlSi2O6)
gemstone
Icy Jadeite (Jade Bangle)
Jadeite, NaAlSi2O6 (Pyroxene group)
gemstone
Serpentine (likely serpentinite)
Serpentine-group minerals, chiefly antigorite/lizardite; commonly with magnetite and carbonate
metamorphic
Grey Slate
Foliated Metamorphic Rock (formed by low-grade regional metamorphism of shale or mudstone)
metamorphic
Polished tiger’s eye
Quartz (microcrystalline SiO₂) with crocidolite-derived iron oxides
mineral
Prehnite
Prehnite (Ca2Al2Si3O10(OH)2)
mineral
Quartz Pebble with Chlorite or Epidote Inclusions
Silicon Dioxide (SiO2) with inclusions
metamorphic
Greenish-gray slate fragment
Slate; fine-grained metamorphosed mudstone, commonly mica- and chlorite-bearing
metamorphic
Slate
Slate (Foliated Metamorphic Rock)
metamorphic
Jade
Nephrite (Ca2(Mg,Fe)5Si8O22(OH)2) or Jadeite (NaAlSi2O6)
gemstone
Slate
Slate (foliated metamorphic rock)
metamorphic
Pale green mica-rich rock (possibly chlorite schist)
Likely chlorite schist; identification is uncertain from the photograph
metamorphic
Greenstone (likely chlorite-rich metamorphic rock)
Chlorite schist/greenstone; possible actinolite- or epidote-bearing assemblage
metamorphic
Epidote in Matrix (Dragon Stone variant)
Epidote with Quartz/Feldspar (Ca2(Al,Fe)3(SiO4)3(OH))
metamorphic
Epidote
Epidote (Ca2(Al2,Fe3+)(SiO4)(Si2O7)O(OH))
metamorphic
Gold in Quartz Ore
Hydrothermal Quartz with native Gold (Au)
mineral
Epidote
Epidote (Ca2(Al2,Fe3+)(SiO4)(Si2O7)O(OH))
metamorphic
Greenstone
Greenschist (containing chlorite, epidote, and actinolite)
metamorphic
Greenstone
Metabasalt / Metamorphosed Igneous Rock
metamorphic