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<p>[QUOTE=&quot;desertgem, post: 819404, member: 15199&quot;]Intercept (tm) products of corrosion control originated with inventions and patents at Lucent labs ( AT&amp;T ) for packaging made of polymer bound reactive metals to &quot;intercept&quot; corrosive compounds such as sulfides and bind them chemically, thus removing them from circulation within the sealed plastic bag( U.S. Pat. No. 4,944,916) issued to Franey However, this reactive metal coating was semi-opaque and rather expensive ( and to me rather ugly). Then after exposure in the coin press, a patent was granted to bind the reactive component to paper and other cellulose products. Here is a patent that explains this process and which led to the introduction of intercept (tm) coin products.</p><p><br /></p><p><a href="http://www.freepatentsonline.com/6593007.html" target="_blank" class="externalLink ProxyLink" data-proxy-href="http://www.freepatentsonline.com/6593007.html" rel="nofollow">http://www.freepatentsonline.com/6593007.html</a></p><p><br /></p><p>This process is not forever. There is a set amount of reactive material in the cardboard used for albums and boxes, and once it is fully reacted, it can not be reactivated, and also there is little indication as to how much reactive power is still present. Just an estimate in number of years it could protect under normal conditions. If you live in a heavy industrialized area, it would be quite less. </p><p><br /></p><p>&nbsp;&nbsp; A sacrificial anode is basically the low tech answer to the above product. The more active metal is more easily oxidized than the protected metal and corrodes first (hence the term &quot;sacrificial&quot;); it generally must react nearly completely before the less active metal will corrode, thus acting as a barrier against corrosion for the protected metal.</p><p><br /></p><p>&nbsp;&nbsp;&nbsp; Since the post 1982 cents have a coating of pure copper, it could qualify for this purpose, especially if it was protecting copper containing coins that by having developed a patina would be less reactive than pure copper. But to make the copper sacrificial coin more attractive, it should be abraded and&nbsp; cleaned severely prior to use. </p><p><br /></p><p>&nbsp;&nbsp; So here is how I approached this project. I took a damaged 2009 Lincoln cent and used acid dip and physical scrubbing with a scrub brush. I decided not to use a metal brush as the copper layer is thin. The coin looked like this :</p><p><br /></p><p><img src="http://i455.photobucket.com/albums/qq279/desertgem/anodeobvb4.jpg" class="bbCodeImage wysiwygImage" alt="" unselectable="on" /></p><p><br /></p><p>and this</p><p><img src="http://i455.photobucket.com/albums/qq279/desertgem/anoderevb4-1.jpg" class="bbCodeImage wysiwygImage" alt="" unselectable="on" /></p><p><br /></p><p>I put it into a SD plastic ( probably polypropylene) holder that I had drilled 4 holes. More small holes would be better, maybe try that also.</p><p>and inserted the coin. </p><p><br /></p><p><img src="http://i455.photobucket.com/albums/qq279/desertgem/anode1.jpg" class="bbCodeImage wysiwygImage" alt="" unselectable="on" /></p><p><br /></p><p><img src="http://i455.photobucket.com/albums/qq279/desertgem/anode4.jpg" class="bbCodeImage wysiwygImage" alt="" unselectable="on" /></p><p><br /></p><p>After 10 days leaving it on the table, I have the following appearance.</p><p>left lid still closed, right: lid open.</p><p><br /></p><p><img src="http://i455.photobucket.com/albums/qq279/desertgem/anodeobvcomparison.jpg" class="bbCodeImage wysiwygImage" alt="" unselectable="on" /></p><p><br /></p><p><br /></p><p>and : reverse</p><p><br /></p><p><img src="http://i455.photobucket.com/albums/qq279/desertgem/anoderevcomparison-1.jpg" class="bbCodeImage wysiwygImage" alt="" unselectable="on" /></p><p><br /></p><p><br /></p><p><br /></p><p><br /></p><p>Here is the before and after reverse photos together</p><p><img src="http://i455.photobucket.com/albums/qq279/desertgem/anoderevcomparisonb4andafter-1.jpg" class="bbCodeImage wysiwygImage" alt="" unselectable="on" /></p><p><br /></p><p>&nbsp;</p><p>The areas of toning, representing sacrificial reaction with environmental gases shows the amount that would have been available to react with the coins you were trying to protect. </p><p><br /></p><p>If you use albums or zip locks these can be added to the bags, or even attached to the album covers. Several can be put into 2x2 boxes, safety deposit boxes, etc. to have added protection. It is easy to check them as to the tone, and replace them or just scrub and acidify them down again. Be sure to remove all cleaning chemicals and dry well. I don&#039;t want to confuse the issue, but I did rinse them in acetone, and allowed to air dry , before inserting into the holder to remove any surface water and contaminants.</p><p><br /></p><p>&nbsp;I purchased 100 of the holders from an ebay dealer in HK, and they were here a week later for total of $18, including shipping. So a few cents for chemicals, 19 cents in parts, and a little labor. </p><p><br /></p><p>Hope this helps, and the patent above is interesting reading.</p><p><br /></p><p>Jim[/QUOTE]</p><p><br /></p>

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