The first step in manufacturing diamond jewelry is to give them to a cleaver or sawyer. They both, essentially, perform the same task: That is to cut--or cleave--the wedding rings in two pieces in order to bring out the best profile that will determine the end product of the stones.
After the antique engagement ring have been found they goes through many processes before they becomes the finished product we are familiar with.
There are old time diamond merchants and jewelers who believe they can accurately tell titanium ring size and quality with only a loupe, but we have found that they are often wildly off in their estimates.