The People where I buy salt told me a yard of pure salt weighs about a ton or a little more, I don't knoe for sure though because they dont weight the truck after they load it. It sags my 3/4 ton pu like it's about a ton though. there was a thread on here not too long ago with the unit weight for salt in it.
My pocket reference book lists fine salt as being 2025lbs per cubic yard,and course salt as 1350 lbs per cu. yd.either way salt is much lighter than wet course sand at 3510 lbs per cu. yd.I can feel the difference when my hopper is heaped with sand,A yd of salt wont squat my truck,a yd of sand sure does.