Process manufacturing produces co-products and by-products. A co-product is a saleable end item that results from a process. A by-product is a material of value that is produced incidental to or as a residual of the process.
D. a rock with metamorphic minerals but no foliation or lineation. A shale is metamorphosed into three rock types: (1) a banded gneissic rock; (2) a rock with small mica crystals with a shiny aspect; (3) a very shiny rock with large mica crystals; and (4) a dull slate with cleavage. Which of the following lists these rocks in order of increasing metamorphic grade?
Oil shale. The term oil shale generally refers to any sedimentary rock that contains solid bituminous materials (called kerogen) that are released as petroleum-like liquids when the rock is heated in the chemical process of pyrolysis.