I purchased this some years back from a lady in Massacheusetts because she informed me that it belonged to Joseph Smith Sr. (the Father of the Founder of the Mormon Church).  It is made of solid copper, 6 and 1/2 inches high and 2 inches wide  It is strung on a plastic holder, because it originally came on a tree stick that got broken and had termites, so it had to be discarded.  The only thing I had in the house was this white plastic string holder.  The Copper Bob has an antique leather pouch to attach to a belt.  A nice antique collectibe.  I don't have a certificate of authenticity that it belonged to Joseph Smith Sr. and even if provable, I don't think the Church of LDS would offer me one.  If you hold it in your hand, you can feel the antique Joseph Smith energy within the instrument.