The Diamond edge model razors that I have are from 1880 to around 1895,they are 1/4 hollow,with a spine ground to a pyramid shape.They have the words Diamond Edge stamped into the blade face on the mark side they are in 6/8 and 7/8 sizes.Some regrinds from the period dont have the stamping they are usually reground to 1/2 hollow.Some of them have a very attractive etch with part of the blade frosted,and the wording in bright letters.They make excellent shavers,and Joe can regrind these into very nice razors if you have one that has had all the goodie honed out.I really like these razors,and so I have quite a few

Best Regards Gary