For those who are knowledgeable in such things. Is there anything unusual about conserving a lead coin prior to TPG submission? For a non-copper base metal coin, typically I would just use an acetone soak. This is my first lead coin though, so I'm not sure what would give the best results.
Lead coin!? Never encountered one. Didn't even know such a thing existed. Is it an ancient? Best guess (but ONLY a guess), acetone should not affect it. But I suggest you wait for someone else's opinion.
Lead tends to oxidize to (duh!) lead oxide, which is a white powdery looking mess. To prevent it, and I use this ONLY for lead, I actually recommend a VERY light machine oil. I have an old bottle of Kodak Light Machine Oil, which is a beautiful product of a bygone era that was used by people who serviced movie projectors. It is the most residue-free oil I've ever encountered. I recommend AGAINST using a TPG in this case.
Thanks for the advice. I'm on the fence regarding the TPG submission. My other trials from this period are raw, but they are trials of relatively available types that I have gem examples of. This one is a trial of a very rare and expensive coin that I am unlikely to acquire an original of anytime soon.
I have a lead trial strike of a Red Rose Coin Club medal (Lancaster, PA) from around the mid-70's and I gave that the Kodak Light Machine Oil treatment, after brushing away some oxide, and it still looks like it did the day I treated it, which is about 7 years now. I also own one of five misspelled Joseph Wharton medals from the same club, struck in pure copper to distinguish them from the bronze and .999 silver ones made after the dies were redone correctly spelling "Wharton". The copper ones say "Warton". The club retained one, I have one, last I heard Kerry Wetterstrom of Classic Numismatic Group (former publisher of The Celator) has two, and I'm not sure who has the fifth one. All but the club-retained one are in ICG slabs. 2 are PF67 and 2 are PF68. I have one of the 8's.
Jaelus, if I may ask, exactly what is it you want to accomplish ? I'm assuming that you'd like to authenticate the trial strike, is this correct ? If it is, a TPG may not be and probably isn't your best bet, depending of course on exactly which ducat it's a trial strike of. Your best bet would probably to track down who the leading expert is on those particular ducats - and ask him to authenticate your trial strike for you. For Netherlands ducats, I know exactly who you need to ask. For others, not so much, but I may be able to help find out.
I appreciate the offer, though I'm not questioning the authenticity in this particular case as I have provenance on the piece, as I do with my other trial strikes as well. I just like uniformity. The rest of my set is NGC and I'm building a custom registry set. Though trials are admittedly somewhat of an outlier for that set, if it was slabbed it would be more easily stored and displayed with the rest of the set (especially for educational displays). It bugs me that my patterns and proofs are slabbed but my trial strikes are not.
I haven't been able to source any of the Kodak light machine oil, but I found https://www.grainger.com/product/STARRETT-Mineral-Machine-Oil-2ZVL1. Does that seem comparable to you?
I am going to try that stuff. My dad (departed this past August) used to say that the Kodak stuff was whale oil, but he was a wisecracker and it wasn't always clear if he was having fun at your expense, so there's that. The Kodak stuff was in a deep brown glass bottle and was applied with a long thin steel pin attached to the screw cap.