The sides and bottom of the keyway should be surfaced true with the file. If a keyway is to be cut by hand through a bore, as in a pulley or gear-wheel bore, its width should be marked with a T-square. This head is also driven by a key which engages a keyway in the boring-bar. The rod end should be planed to thickness for the brasses and of equal thickness on each side of the keyway. The flat key is used where it is necessary to secure the wheel more firmly without weakening the shaft by cutting a keyway in it. A much more usual method, however, is to employ slotting or keyway drills.
 Igneous, metamorphic, and sedimentary are descriptive terms used to  classify types of rocks, not minerals su â¦ ch as diamond.     Diamond is accepted as a valid mineral by the International  Mineralogy Association.
A metamorphic rock is an igneous, sedimentary, or ano â¦ ther metamorphic rock that has either been squeezed by incredible pressures deep underground and/or has been exposed to very high temperatures, altering its structure, mineral alignment, mineralogy, and possibly its chemistry. 3 people found this useful.ituminous coal is a sedimentary rock. Anthracite coal is considered a metamorphic rock. 5 people found this useful. Edit. Share to: 1  The Periodic Table of Elements Life is sustained by a number of chemical elements.