Phyllite

Phyllite ( from Ancient Greek φύλλον phyllon "leaf" ), phyllite slate, Tonglimmerschiefer or Urtonschiefer is a finely crystalline, thin chief -engined, usually bladed Metapelit with a sericite- share of more than 50%, of and in addition to mica, quartz, feldspar, chlorite, augite, tourmaline may contain iron oxides as mineral phases.

As a low-grade metamorphic rocks of the greenschist facies phyllite emerged by regional metamorphism of slate. Compared to the slate, which is not or only very slightly metamorphic overprints and therefore still one of the Sedimentiten to phyllite is characterized by the absence of the original (primary) clay minerals. The sericite (muscovite ) portion produces a silky shine on the slate surfaces. The color ranges from dark gray to gray- black, and greenish gray and purple gray before coming.

Often, in addition to a Hauptschieferung, the so-called S1 foliation, which is attributed to the first deformation event, narrated more foliations as consequences of later tectonic events as surface structure in the phyllite. S1 foliation is usually verfaltet in this case. The location of the stack (SS ) of the original mudstone can be determined only occasionally striking at phyllites based material and color changes.

As part of the regional metamorphism is phyllite ( the amphibolite facies in the pressure-temperature field) converts at higher pressures and temperatures in mica schist to when the rock-forming minerals of the phyllite zoom by crystal growth to the extent that they are visible with a magnifying glass or with the naked eye are.

Phyllites occur in many areas of the world where shales and other fine-grained parent rocks were deformed and heated. Thus, large parts of the Saxon and Thuringian Slate Mountains are composed of phyllites.

Phyllite with quartz, as is found in southern Finland, since the 16th century is used as a grindstone use.