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<p>[QUOTE=&quot;Keith Richey, post: 2719765, member: 87047&quot;]Also.</p><p>Dear Mr. Diamond:</p><p><br /></p><p>“I’ve consulted with our technical experts regarding the cause of the appearance of the coins in the photographs attached with your e-mail.</p><p><br /></p><p>The samples shown in the photos were the result of a loss of protective atmosphere or being stuck in the annealing furnace for a prolonged period of time, or both.</p><p><br /></p><p>This would result in migration of the copper and nickel to the surface of the blank. Since there is three times as much copper then nickel in the outer layer of these coins, the diffusion of copper to the surface will be significantly greater than the diffusion of the nickel, resulting in the reddish appearance noted. </p><p><br /></p><p>Depending on the time the blank sits in the annealer, and whether it is exposed to oxidizing conditions, various reactions can occur. This will result in the type of phenomenon shown in the photos, where a distinct layer of material forms on the blank surface (primarily copper, with a high degree of oxidation), which is quite brittle, and will break off in pieces. This will expose the original blank surface, which would also be oxidized, but closer in color to the original alloy. We have seen these types of blanks but only infrequently.[/QUOTE]</p><p><br /></p>

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