Hello all! I have what appears to be a silver proof National Bicentennial Medal. I am at my wits end trying to determine silver content, etc. The medal was issued by the American Revolution Bicentennial Administration (ARBA), presumably in 1976. The ARBA was set up under Federal law 93-179. It is definitely proof cameo. It is 1 1/2" in diameter. I didn't weigh it because it is in a mint-issued capsule that I can't get open. ARBA's made reports to Congress which I have found are not available online, either through Google Books or the National Archives website. I was trying to find out when these were minted, in what numbers, and what the ASW was. eBay was no help. Sellers there are confused too. Some say the medal is 1 troy ounce of 90% silver. I have seen others claiming that the coin is more than an ounce of sterling silver (.925), that when calculated out, comes to 1 ounce of pure silver. I've visited some of the exonumia sites with mixed results. The U.S. Mint online archives were not any help either. Most of their documents focused on the America’s First Medals series that I believe came out before my medal. Online, I've found a scan of the original order form for this medal, primarily in the gold version with some reference to the 1 1/2" silver version without any mention as to purity or silver content. Does anyone have any OFFICIAL, U.S. Mint info on how many of these were minted and at what weight and purity? Do you know of a good book on exonumia that would have had this info? Many thanks for your replies!