Earth Sciences 1089F/G Lecture 3: Earth Sciences- Febraury 9th
7 Oct 2016
School
Department
Course
Professor
Document Summary
Clay: from weathering product to art medium: a member of a large group of fine-grained platy minerals related to micas, a mixture of minerals with clay-sized particles, mass of minerals (mostly clay) that behave plastically when wet. Hard, brittle, nonmetallic material made from clay and other earth minerals. Contains minute silicate crystals suspended in glassy cement. +ions that bond these sheets together (h, k+, fe, ma) Properties of clay: ability to be shaped: Clay mineral crystals have a platy habit and perfect basal cleavage, therefore, both intact and broken clay mineral grains tend to be wide and flat (like plates) Under weak stress, the plates slide past one another, allowing the clay to deform readily (especially when lubricated with water: cohesion. Small amounts of water cling to the particles. Surface tensions produced by the water allows particles to stick together. Produced by the weathering of other minerals, particularly feldspars. Clay body: several different clays are blended together; used in ceramics.
