Mineral, Often Found As A Rock (Metamorphic)

Iron-stained Quartzite

Quartzite with Limonite/Hematite staining (SiO2 with FeO(OH)·nH2O)

Micaceous Rock (likely Muscovite Schist/Gneiss or a Muscovite-rich Specimen)

Predominantly Muscovite (KAl2(AlSi3O10)(F,OH)2), often found in rocks like Muscovite Schist or Muscovite Gneiss.

Given the appearance, it's likely a fragment of an igneous or metamorphic rock composed of multiple minerals. Without specific diagnostic features, it's difficult to give a common name other than 'crystalline rock fragment'. If pressed to guess based on the granular, somewhat light and dark speckled appearance, it could be a fragment of granite or a related intrusive igneous rock.

As a rock fragment, it does not have a single scientific mineral name; rather, it's a piece of a rock which is a combination of minerals. If it were granite, its main mineral composition would be quartz (SiO2), feldspar (e.g., KAlSi3O8 - orthoclase, (Na,Ca)(Al,Si)4O8 - plagioclase), and mica (e.g., KAl2(AlSi3O10)(OH)2 - muscovite or K(Mg,Fe)3AlSi3O10(OH)2 - biotite), among others.

Quartzite

Quartzite (Primary mineral: SiO2)

Gneiss

Gneiss

Quartzite (River Pebble)

Metamorphosed Quartz Sandstone (SiO2)

Clear Quartz (Rock Crystal)

Silicon Dioxide (SiO2)

Quartz (Pebble)

Quartz (SiO₂)

Milky Quartz

Silicon Dioxide (SiO2)

Milk Quartz (White) and Yellow Aventurine (Yellow)

Silicon Dioxide (SiO2)

Quartz (Milky Quartz)

Silicon Dioxide (SiO2)

Quartzite

Quartzite (SiO2)

Lapis Lazuli

Lapis Lazuli (Complex aggregate mainly of Lazurite: (Na,Ca)8(AlSiO4)6(S,Cl,SO4,OH)2)

Gneiss

High-grade regional metamorphic rock (Foliated)

Clear Quartz Crystal

Quartz (Silicon Dioxide, SiO2)

Chert (Smoky variety)

Microcrystalline Quartz (SiO2)

Chert (White Chert / Flint)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Chert (Flint)

Chert (Microcrystalline Quartz, SiO2)

Jade (Nephrite or Jadeite)

Nephrite (Ca2(Mg,Fe)5Si8O22(OH)2) or Jadeite (Na(Al,Fe3+)Si2O6)

Biotite Gneiss

Gneiss (complex mixture including Biotite K(Mg,Fe)3AlSi3O10(F,OH)2 and Quartz/Feldspar)

Metagabbro / Epidote Gneiss

Epidote bearing Hornblende Gneiss

Amethyst

Silicon Dioxide (SiO2) with iron impurities

Unakite

Epidotized Granite

Jade (Nephrite or Jadeite)

Nephrite (Ca2(Mg,Fe)5Si8O22(OH)2) or Jadeite (Na(Al,Fe3+)Si2O6)

Schist (Micaceous Schist)

Schist (comprising Muscovite/Biotite mica, Quartz, and Feldspar)

Greenstone

Greenschist (metamorphosed mafic igneous rock)

Smoky Quartz

Silicon Dioxide (SiO2) with aluminum impurities

Quartzite

Quartzite (SiO2)

Chert (and/or Flint)

Microcrystalline or cryptocrystalline Quartz (SiO2)

Quartzite Pebble

Meta-quartzite

Chert (Honey Chert / Flint)

Silicon Dioxide (SiO2) - Cryptocrystalline Quartz

Bronzite

MgSiO3 (Enstatite with 10-30% FeSiO3 in solid solution)

Quartzite

Quartzite (SiO2)

Greenschist

Greenschist facies rock

Milky Quartz

Silicon Dioxide (SiO2)

Gneiss (Metamorphic Rock)

Gneiss

Pyrite (on Quartz/Host Rock)

Iron Sulfide (FeS₂)

Greenschist (containing Epidote and Quartz)

Greenschist (Epidote-Chlorite-Actinolite Schist)

Acicular Azurite (indicated by deep blue, fibrous/fuzzy appearance)

Azurite (Copper Carbonate Hydroxide) - Cu3(CO3)2(OH)2

Quartz Pebble

Silicon Dioxide (SiO2)

Green Tourmaline

Verdelite (Silicate mineral); Na(Li,Al)3Al6(BO3)3Si6O18(OH)4

Serpentine (Serpentinite)

Serpentinite (Mg, Fe, Ni, Al, Zn, Mn)2-3(Si, Al, Fe)2O5(OH)4