Struck at the Philidelphia ANA Convention March 23, 2000 on the refurbished US Mint Coin Press which was the first steam press in the US Mint. Most were struck in copper, so this is considered an "off-metal".
 
.8924 Coin Silver
11 grams

This piece is from Gallery Mint Museum Archive Set #4 and are mostly, if not all, the corresponding struck piece to that number. (i.e. #4 is the 4th piece struck from the dies). Archive sets were struck outside regular mintage numbers.