Mark McGwire 3 Coin Proof  Set – This is  a commemorative set in recognition of McGwire breaking Maris' single season Home Run record. This is a matched numbered set, each coin bearing the same number. One coin is made of one Troy ounce of .999 Fine silver, the second is one Troy ounce of .999 Fine Silver with a 24K Gold overlay and the third is solid Bronze. This is a very limited edition set, only 500 matched numbered sets produced by Highland Mint.