Iâve come across a historical footnote on the English language and I thought everyone would get a kick out of it. Up until about 2 hundred years ago, there was a 27th letter in the English language. This letter is still in common use today and I would bet that you have used it recently. But this letter is no longer considered a letter; it is now regarded either an abbreviation or punctuation. Iâm talking about the (&) ampersand.
Gneiss is a medium to coarse-grained, irregularly banded rock with only poorly developed cleavage. The light and dark bands (gneissic banding) are alternations of felsic vs. mafic layers. Slate is a product of low grade metamorphism (not terribly great burial temperatures and pressures are required).
Grain, esp. oats or wheat, hulled and coarsely ground; in high milling, fragments of cracked wheat smaller than groats. 4. (Geol.) A hard, coarse-grained siliceous sandstone; as, millstone grit; - called also gritrock and gritstone. The name is also applied to a finer sharp-grained sandstone; as, grindstone grit. 5. Structure, as adapted to grind or sharpen; as, a hone of good grit.