This brooch is a replica of a late medieval brooch, inscribed with Latin phrases. At the front it says “iaspar; Melchior; balthazar”, the names of the three wise men, and on the backside it says “ihesus nazaren[us] res iudeoru[m]” (Eng.: Jesus of Nazareth, King of the Jews).
The original find is exhibited in the Victoria and Albert Museum in London (http://collections.vam.ac.uk/item/O15211/ring-brooch-unknown/) and is from England or France and dates back to ca. 1350-1450.
The diameter of the Medieval brooch with inscription is 2.7 cm and is available in bronze and silver-plated.