the best person in the world. he's one in a million. he's polite, kind, thoughtful, and freaking hilarious. there is never going to be anyone like him. i love him more than any boy.
Slate is a rock, so you won't find it listed on the Mohs Scale, because that scale of hardness applies to minerals. I'll go out on a limb though, and suggest that slate is probably around 2 to 3 or so, but this will be variable, depending on the quality of the slate, and degree of weathering, etc. Slate is a rock, so you won't find it listed on the Mohs Scale, because that scale of hardness applies to minerals.
Whilst it can be proven that the centre nail fixing of double lap slates is a very efficient method of fixing slates to resist the most severe wind conditions, it is impossible to centre nail the top row of slates. The inappropriate detailing of the top slate fixing is the most common problem found on a slate roof.In previous articles we have looked at the effect wind suction has on the exposed section of the slate and how the top of the slate stops the slate rotating about the nail fixings in the middle.he additional height of the second batten should be equal or slightly greater than the nominal thickness of the top course of slates. . It is common to see a 32x25mm tile batten turned on edge for the second batten, or a standard batten with an additional 6mm lath nailed to it, with a 6mm thick natural slate.