I'm pretty sure the spawn points of mining deposits are realy old and not legit. For example, you find Silver Deposits in Ashenvale every 5 meters without problems, they are not rare at all and the spawns are the same as they were before in Databases of Ludmilla,old MaNGOS servers etc. (you could always farm on other private Servers silver ore in Ashenvale on mass).
You should check and change them in the whole world, would be very nice.
I'm not sure, but there were already good databases with other spawn points (and a blizzlike spawn system of the mining deposits?) some years ago.
Correct me if I am wrong.
regards