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    'Nonsense Prototype Disk' Pair, MS66
    With Martha Washington Design

    (1999) Sacagawea Prototype Composition Disks MS66 NGC. The composition disks were resurrected Martha Washington dies used earlier in 1965 for similar composition tests. In 1999 as the Mint was preparing for the new Sacagawea dollars, they again issued prototypes.
    An accompanying letter from the Department of the Treasury explains the new disks that carried no actual denomination:

    "The Purpose of these prototype alloy samples is to field test two (2) alloy systems that the Mint has prepared for the new dollar coin. We need to get feedback from the industry relative to any tokens, foreign coins, or any other materials that may result in slugging problems. (In other words, these samples should not be accepted in any of your current electronic coinage discrimination channels.)"

    The two pieces offered here are the "N" and "O" composition test disks sent out by the Mint. We believe that this is the first time both alloy systems have been offered together. These test disks are included in the 10th edition of the Judd reference as Judd-2184 to Judd-2187, although the numbering may require revision.

    (1999) 'N' Composition Test Disk MS66 NGC.
    Plain Edge. This disk has a composition of 77% copper, 20% zinc, and 3% nickel. It has the letter N etched twice in the obverse field for identification purposes. The brilliant yellow surfaces have satiny luster.

    (1999) 'O' Composition Test Disk MS66 NGC.
    Plain Edge. This disk has a composition of 73% copper, 24% zinc, 2% nickel, and 1% manganese. There are no letters etched in the fields. Fully brilliant lemon-yellow with prooflike surfaces.

    The 10th edition of Judd records the following:

    Judd-2184 Intermittently Reeded Edge. Copper-nickel clad copper.
    Judd-2185 Plain Edge. Manganese-brass coated copper-clad metal.
    Judd-2186 Intermittently Reeded Edge. Manganese-brass coated copper-clad metal.
    Judd-2187 Reeded Edge. Manganese-brass coated copper-clad metal.

    Neither of the two pieces in the present lot exactly matches any of the four descriptions in the Judd reference. A review of the Judd numbers for these various issues is probably in order.

    Auction Info

    Auction Dates
    May, 2009
    28th-31st Thursday-Sunday
    Bids + Registered Phone Bidders: 18
    Lot Tracking Activity: N/A
    Page Views: 1,002

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