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    Primary Source Material for 1964-1965 Detaclad Bonding
    Includes 'Franklin Quarter,' Pollock-5391

    (1964) Detaclad Explosion Bonded Franklin Quarter, Three Square Planchets, Hand-Written Note, and Photo Album. During 1964-1965 an effective method was needed by the Mint that would bond an outer layer of nickel or silver to an inner core of copper, what we know today as "clad coinage." The problem, as seen by Mint officials at the time, was that coin collectors were pulling too many coins from circulation and were the cause of a coin shortage. One solution was to eliminate mintmarks, thus decreasing collecting pressure on modern issues. Another solution of the dwindling stocks of precious metals was to remove silver from the dime and quarter, and to gradually do so from the half dollar. The solution, however, had to satisfy the vending machine industry (and AT&T) to ensure that the new "clad" coins would work properly when they replaced the traditional silver composition coins.

    A process was developed called "explosive bonding." Cobbling together quotes from two internet sources, this method of bonding is explained by one source as, "The process does not melt either metal, instead it plasticizes the surfaces of both metals, causing them to come into intimate contact sufficient to create a weld." Another explains that, "Large areas can be bonded extremely quickly and the weld itself is very clean, due to the fact that the surface material of both metals is violently expelled during the reaction." Explosive bonding was only used for a few years. This method was used by DuPont and Revere to make experimental clad coinage.

    Very little has been published about this period of experimentation. This particular lot is original source material compiled and written by Richard M. Brown, who was there at the time and worked at Revere's Michigan Division. Included is a clad "Franklin quarter," Pollock-5391. The experimental coin has the likeness of Franklin on the obverse, the reverse has the DuPont logo in the center, surrounded by the most interesting legend: THIS TOKEN MADE FROM EXPLOSION BONDED "DETACLAD". The piece is uncertified and we grade it MS62. Also included are three square pieces of Detaclad, all unstamped. One is 19 mm x 19 mm and thin, one is 20 mm x 20 mm and just slightly thicker, the third is 21 mm x 21 mm and a thick 6 mm. There is also a four-page (small pages) hand-written note about the development of clad coinage. Also of significant interest as original source material is a 8 ½ x 11 dog-eared binder from 1966 titled "A Pictorial Summary of the Conversion of Cupro-Nickel Coinage Metal for U.S. Mint." There are 21 color photographs included and a 1966 article from Ordnance titled "Explosive Cladding." Of significant interest to the numismatic researcher.
    R. M. Brown's daughter, a national conservation medalist, will donate the proceeds from this lot to Green!USA, a non-profit organization that she founded.

    Coin Index Numbers: (NGC ID# 7HV6, PCGS# 661000)

    Auction Info

    Auction Dates
    June, 2013
    5th-9th Wednesday-Sunday
    Bids + Registered Phone Bidders: 13
    Lot Tracking Activity: N/A
    Page Views: 2,037

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