Too loose or too tight? Ring sizing is a fairly straight-forward process, and one of the most common repairs. It involves either adding or removing a piece of metal from the shank of a ring to increase or decrease the diameter, or ring size without changing the ring's appearance. Metals such as gold, silver and platinum are the only types that can be sized by a fine jeweler. Titanium, stainless steel or tungsten cannot be sized and must just be made in a new size.