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<p>[QUOTE=&quot;SuperDave, post: 2487325, member: 1892&quot;]It&#039;s quite simple, really, as long as you acknowledge and plan safely for acetone&#039;s flammability and volatility. The hard part for many is making the decision to employ it properly, because there are as many situations when you don&#039;t want to remove the gunk as situations when you should. You can&#039;t forget that the coin surfaces under gunk will not have skinned (using jeffB&#039;s definition) the same way the still-exposed surfaces will have, and if you successfully remove the gunk you&#039;ll be left with patches of cleaned-looking surfaces (because you just cleaned them) which will be obvious indicators of treatment. The whole point of this is - for most coins, ancients use another set of rules - to come up with a nicer-looking coin <b>which doesn&#039;t look cleaned</b>. PVC plasticizer reactions, however, require treatment regardless of any other factor, because they&#039;re certain eventual death for the coin if left untouched.</p><p><br /></p><p>Here&#039;s how I go about it, understanding I&#039;m a bit....obsessive about the process:</p><p><br /></p><p>I employ a shot glass of a size small enough to prevent the coin from laying flat, so acetone can touch every part of it. I do not use acetone in &quot;spot&quot; fashion; the majority of what you&#039;re using it for is an indication the whole coin needs to soak, and I soak the whole coin (at least the first step). If there&#039;s PVC, assume the whole coin has PVC. It&#039;s not visible until the chemical reactions have advanced. I employ a small square of glass as a cover for the shot glass, and the glass-on-glass contact is normally sufficient to prevent evaporation for long enough to get the job done. The soak sits next to an open bathroom window (few flammables in a bathroom, and usually good ventilation; I run the fan if one&#039;s there as well). Air movement is key.</p><p><br /></p><p>I use a large rubber-tipped hemostat to handle the coin into and out of the acetone, because the small glass requires precise handling and you haven&#039;t felt pain until acetone touches an open cut on your hand. <img src="styles/default/xenforo/clear.png" class="mceSmilieSprite mceSmilie1" alt=":)" unselectable="on" unselectable="on" /></p><p><br /></p><p>Like so (not mine; this one&#039;s 6.5&quot; and mine is 10&quot; long):</p><p><br /></p><p>[ATTACH=full]525826[/ATTACH] </p><p><br /></p><p>The first &quot;click&quot; of connection on the handles is enough on mine for a nice positive grip, and you ensure they touch only the rim, and for my use that can be done without fear of harming the coin. Yes, the acetone will eventually eat away the rubber but if you rinse them <i>immediately</i> after use they&#039;ll last a long time. Mine are ten years old and still active.</p><p><br /></p><p><br /></p><p><br /></p><p>If I&#039;ve decided acetone is necessary, the first soak is <b>always</b> overnight. Acetone won&#039;t remove anything of toning or genuine chemical patina, and this is probably overkill on my part, but that&#039;s what I do. The following morning, I remove the coin and swish it in a fresh acetone bath in about a baby food-size jar. Acetone is <b>one-time use only</b>, and you destroy at after each use (if it&#039;s done its&#039; job, there is nastiness suspended in it), so even though it&#039;s cheap you want to economize if you can. I&#039;ve burned entire quarts on single coins....</p><p><br /></p><p>So, I then inspect the coin to see what has and hasn&#039;t been accomplished. In extreme cases, one might need to work on the surface of the coin with something sharp to pick at an infestation; I do this with the coin in a shallow acetone bath, employing rose thorns and a table-standing magnifier. Good ventilation is a <b>must</b> for this process, because you&#039;re exposing yourself and your environment to a fairly high concentration of evaporated acetone - a pie-pan sized receptacle with 3/4&quot; of acetone in a layer will evaporate completely in <b>minutes</b>. I have an N95-rated fullface respirator (acetone will attack your eyes rather quickly) with organic vapor cartridges - cost me $30 - for occasions when I&#039;m feeling <b>really</b> paranoid.</p><p><br /></p><p>If any visible PVC (I&#039;m deliberately concentrating on PVC, because I rarely elect to remove anything else from a coin that acetone is capable of removing) is left, the coin gets another overnight soak. Lather, rinse, repeat.[/QUOTE]</p><p><br /></p>

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