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<p>[QUOTE=&quot;lrbguy, post: 3979584, member: 88829&quot;][USER=95174]@BenSi[/USER], I have to disagree with our colleagues on the list a bit on the question you have posed.</p><p><br /></p><p>I seldom clean a coin these days, mainly because the coins I usually buy don&#039;t need it.&nbsp; But there are exceptions, and for those I rely upon a technique I developed for myself back in the 1990s.&nbsp; I am currently working on a denarius of Manlia Scantilla <a href="https://www.cointalk.com/threads/my-top-10-women-of-rome-acquisitions-for-2019.352706/" class="internalLink ProxyLink" data-proxy-href="https://www.cointalk.com/threads/my-top-10-women-of-rome-acquisitions-for-2019.352706/">see here</a>.&nbsp; The value of my coin is at the same grade as your Byzantine piece, but is more fragile and subject to defacement because it is made of silver.&nbsp; Read on and see what you could do with a bit of effort.</p><p><br /></p><p>The tools are quite straightforward but will require some considerable practice to use safely and effectively: a binocular microscope and a set of different sized fine point steel needles.&nbsp; A 10x setting on the scope will give you the lay of the landscape, and 30x will allow you to discriminate the composition of the layers of accretion from patina or bare metal surface.&nbsp; More than this is too much detail for this technique, and not only unnecessary but also a step toward disaster.&nbsp; A lens not only magnifies object size, but also the apparent speed and distance of movement.</p><p><br /></p><p>Here are before and after detail shots of the coin after I had worked on it for a couple of hours.&nbsp; The upper image is just as it was received from CNG.&nbsp; You will notice that there are numerous scratches already on the coin as it was received.&nbsp; It had been worked on by someone before me, who used a fine wire brush in his toolkit, and an apparently heavy hand.&nbsp; There are no noticeable additional scratches in my after shot, although some of the attentuation is due to a change in the angle of lighting.&nbsp; I was not interested in trying to improve surfaces, but rather to remove accretions and buildup in crevices/</p><p><br /></p><p>[ATTACH=full]1047530[/ATTACH]</p><p>&nbsp;</p><p><br /></p><p>The view of this coin in the shots above is something greater than 10x mag. At 10x the whole coin just barely fits completely within the field of view.&nbsp; &nbsp; This next pic gives a close approximation of what you see at 30x, the usual working magnification.&nbsp; Here you can also see the tip of the finest pointed needle in my kit.&nbsp; Notice that the needle is sharpened on a bevel, which increases its utility on auguring out embedded material.</p><p>[ATTACH=full]1047531[/ATTACH]</p><p><br /></p><p>This next shows the business end of that needle when set to work between the letters of the obverse inscription.</p><p><br /></p><p>[ATTACH=full]1047532[/ATTACH]</p><p><br /></p><p><br /></p><p>Here are broad views of the obverse and reverse so you can see how the original residual scratching stands against the texture of the coin&#039;s surface.&nbsp; It appears to me that the earlier owner who worked on this coin may have attempted to do some smoothing of the scratches s/he was inflicting, particularly on the reverse fields, but gave it off as more trouble than help.&nbsp; The needle in the obverse pics is the large coarse needle I use when I am skimming plain surfaces right up to the edge of lettering.&nbsp; As you can see, it is much too large for working out the fine crevices of figures and within&nbsp; many letters.</p><p><br /></p><p>[ATTACH=full]1047533[/ATTACH]</p><p><br /></p><p>[ATTACH=full]1047534[/ATTACH]</p><p><br /></p><p>It is not necessary nor inevitable to wreck a coin by cleaning it with a microscope and needle.&nbsp; Key to making this work is to develop a &quot;touch&quot; that will allow you to let the needle come into contact with the patina or even the bare surface, without leaving a furrow on the surface.&nbsp; Bronze coins develop a rather hard patina, so they are fairly easy to work with.&nbsp; Silver does not develop the same kind of hard skin and so is very easy to scratch.&nbsp; Easy does it!</p><p><br /></p><p>Fortunately for you, the coin you want to clean up of its &quot;sand patina&quot; (natural or otherwise) is bronze, so once you gain some skill at the technique you can remove it without too much trouble.&nbsp; But at that point you will be confronted by the reality of the surface as it really is below the sand encrustation.</p><p><br /></p><p>Sometime down the road I will show you the next state of my Manlia piece after I have done some more work on it.&nbsp; It won&#039;t be soon, though as my plate is full at the moment.&nbsp; And lest there be any doubt, I only clean coins I personally own.[/QUOTE]</p><p><br /></p>

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