It is the mark of Shafer & Douglas, Newark, New Jersey. The company was established in 1855 by Joseph H. Shafer as Shafer & Swinerton, changing its name in 1869 to Shafer & Douglas when Frederick S. Douglas joined the firm. Rainwater writes: ‘It continued without change until the death in 1899 of Douglas, when it was incorporated. W.E. Shafer, son of the founder, entered the firm in 1904. The last listing found was in 1922. At first they made jewelry of various kinds but on the death of Douglas, the making of jewelry was discontinued and they made rings exclusively’.