These cufflinks are marked "Hecho en Mexico, Sterling 925" with a symbol of the Mexican Eagle #28.  The style of the bell indicates that these are from the time between 1955 and 1980 when the Eagle marking system was abandoned for a newer marking system.  The cufflinks are engraved with Aztec symbols in the edging and the sunburst center.  The finish is a nice subltle grey which offsets the cut away silver.  They have a swivel bar that is marked "Alpaca", which is a metal with more nickle forming the swivel bar than in the sterling tops.  They measure 3/4" in diameter.  SORRY, THIS ITEM HAS ALREADY BEEN SOLD!