Cleavage
Cleavage in Rocks
When a rock cleaves, the strains that produce cleavage are similar to those suffered by layers when they fold over. Cleavage is usually found near the fold’s axial plane, and not parallel to it. The cleavage’s orientation can vary between beds and within folds. Nonetheless, the process is quite similar across a rock’s layers. Therefore, cleavage is a natural process in most rocks.
Cleavage is a complex process that involves two systems. Cytokinesis, a contractile network of microfilaments made from actin, and karyokinesis are both mechanical agents of mitotic division of nucleus. Sea urchins display a close relationship between these two systems during cleavage. During fertilization, the embryo develops a new balance between cytoplasm and nucleus, and cleavage occurs soon thereafter.
One exception to this rule is: Minerals with flat surfaces are not necessarily cleavage planes. The cleavage planes form when the mineral grows and breaks. Quartz, for example, has a hexagonal prism shape and breaks at an irregular angle. Amphibole, on the other hand, is a greenish-black mineral. Although they have similar hardness, their cleavage angles make them distinct from each other.
Minerals that fail along the cleavage planes of minerals are known as “bendy”. These crystals are more difficult to identify than crystals with perfect cleavage. In addition to the direction, cleavage angles can be important clues for identifying a mineral by name. Those that exhibit perfect cleavage have smooth surfaces, while those with poor cleavage tend to have irregular shapes.
The three most common types of cleavage are butt cleavage, side-boob cleavage, and floating clausterite. While all three types of cleavage are beautiful, not all women have them. Some women display their cleavage in different ways. A woman who is more extreme with her cleavage can be a mystery and an ambitious woman. The other two are cleavaged in random patterns.
Fragments resulting from crystal smashing along their cleavage planes will be irregular. Quartz, for example, does not show cleavage. Quartz cross sections will instead have irregular or shell-like shapes. A quartz crystal can be broken down into many different types. They have various shapes depending on their crystallographic structure. A fracture can occur when a cleavage plan breaks.
The cleavage angle of a mineral is one of the most important factors in identifying the species. Interestingly, many minerals do not form smooth flat surfaces when they break. Moreover, the angle between the cleavage plane and stratification plane is correlated with the variation of cleavage with progressive deformation. Vertical cleavages in horizontal straification did not change with folding.
A gemstone’s cleavage is a sign of its toughness and durability. A perfect cleavage is a hallmark of a diamond. Likewise, sapphires and rubies have rough surfaces. These characteristics determine how easy it is to cut these gemstones. The durability of a gemstone is determined by its shape and ease of cutting. Diamonds are the most durable gemstones.