Peter Wright anvils are stamped on the side and measured in english hundred weight ..the first number is stones which is 112 lbs the second is quarter stones which is 28 lbs . the last number is lbs .. So if Marks anvil is marked 1-0-8 it is 120 lbs 112+0+8= 120 lbs . They can also be aged by markings . They are very good anvils and i saw a nice one on a remote colorado ranch last year and another on a wyoming ranch .. I have aquired 3 over the years but they are in recent years spendy as farm auctions have collectors watching .