Slaty cleavage is a pervasive, parallel foliation (layering) of fine-grained platy minerals (chlorite) in a direction perpendicular to the direction of maximum stress. The process produces the rocks slate and
Since the nature of cleavage is dependent on scale, slaty cleavage is defined as having 0.01 mm or less of space occurring between layers. Slaty cleavage often occurs after diagenesis and is the first cleavage feature to form after deformation begins.
SLATY: alignment of microscopic platy minerals – gives a slaty cleavage. PHYLLITIC: foliation of platy minerals that can just be seen with a hand lens. Appears shiny and does not cleave as well because foliation planes may be deformed. SCHISTOSE: foliation defined by minerals that can be seen with the naked eye.
…s-surface, bedding, or crystal orientation; slaty cleavage, a planar structure leading to facile cleavage that is normally caused by the preferred orientation of mica crystals; schistosity, a term used to describe repetitive and pronounced foliation of the type that is present in schists; and lineation, which is any ...
Slate is a hard, fine-grained rock with a well-developed rock cleavage or slaty cleavage caused by the incipient growth of platy (micaceous) minerals, due to metamorphism of fine-grained clastic sediments such as shale and siltstone and also volcanic tuffs.
Slaty Texture
• Rocks with a slaty texture are fine-grained. They have dull surfaces and split apart easily.
Slaty foliation refers to sheet-like layering within a metamorphic rock. This is characterized by millimeter-thick folia/layers in the rock, that are typically formed by the compaction of fine-sedimentary rocks such as mudstone and shale.
Slate derives from low-grade metamorphism of fine-grained, clay-rich sediment. The parent sediment is weak and tends to flow plastically when deformed. This behavior results in cleavage planes and recrystallization.
There are several types of cleavage symmetry seen in nature: radial(echinoderms, amphibians), spiral (mollusks, annelids), Bilateral (ascidians,tunicates), Rotational (mammals).
schistosity, mode of foliation that occurs in certain metamorphic rocks as a consequence of the parallel alignment of platy and lath-shaped mineral constituents. It reflects a considerable intensity of metamorphism—i.e., changes resulting from high temperatures, pressures, and deformation. Related Topics: foliation.
Phyllite is a low- to moderate-grade metamorphic rock that contains aligned platy mica minerals and has slaty cleavage.
Cleavage/Fracture: Sulfur minerals have conchoidal fracture. Conchoidal fracture is aa type of fracture that shows breakage that have smoothly curving surfaces. (7) This type of fracture is typically found in very fine grained minerals. It means that there are no planes of weakness found in the mineral.
Rock cleavage in slates (slaty cleavage) is largely a consequence of abundant, parallel-aligned, very fine- grained mica flakes in the rock. Calcite is the main mineral constituent of the sedimentary rock limestone and of the metamorphic rock marble.
In political science and sociology, a cleavage is a historically determined social or cultural line which divides citizens within a society into groups with differing political interests, resulting in political conflict among these groups.
If the clay is deposited in layers and has a tendency to split along the bedding planes, it is shale. If it is tilted up at a new angle and was compressed so that it spread out and produced cleavage planes at right angles to the direction of pressure, it is slate.
Conclusion. Schist and slate are very similar in that they are made from the same rock types except it is subjected to more heat and pressure. It is often referred to as schistosity because of its large mica flakes. Large crystals cause schist rocks to reflect lots of light which gives it a very shiny appearance.
Slate was formed under low-grade metamorphic conditions—i.e., under relatively low temperature and pressure. The original material was a fine clay, sometimes with sand or volcanic dust, usually in the form of a sedimentary rock (e.g., a mudstone or shale).
Slate is characterized by fine foliation along which it breaks to leave smooth, flat surfaces (often referred to as "slaty cleavage" - not to be confused with cleavage in minerals).
It is easily recognizable due to its fine grains and foliated appearance. Slate has what is described as "slaty cleavage" due to the process of foliation, where pressure forces long and platy minerals to align in layers.
There are three types of foliation: slate, schist, and gneiss. To differentiate between these types, the characteristics of mineral grain size, mineral layer thickness, and mineral grades are categorized.
Slaty cleavage is a pervasive, parallel foliation (layering) of fine-grained platy minerals (chlorite) in a direction perpendicular to the direction of maximum stress. The process produces the rocks slate and phyllite.
Slate is usually formed from mudstone that has been put under pressure and heated up during plate collisions and mountain building. Pressure causes the platy clay minerals to line up parallel to each other and so the rock splits easily into sheets.
Hardness: Slate is a hard and brittle type of rock, although it is smooth to the touch. Major minerals: The main minerals within slate are mica, which appears in small, irregular scaled, chlorite, which appears in flakes, and quartz, which appears in lens-shaped grains.