Button stud

I recently bought this object online. It is 22mm in diameter and the front are from silver with enamel. The back got some kind of fancy spring clip made out of brass. RESTS PATENT are written on the back ans their is a symbol like a rising sun on it. Any idea what this object may be, how old it is and who made it will be welcome.

button back 2.jpg
button back.jpg

So I did some digging on the web. This is a West’s Patent Solitaire Cufflinks Cuff Link from around 1880. Still need to figure out the rising sun mark…