This coin arrived today. It is quite unusual. It is an imitation of the Athenian tetradrachm of the mid to late 5th century BC. It is made of lead. Lead is prone to deterioration when exposed to moisture. Here in California that isn't a major issue, but humid days do occur. Also, there is the safety issue, since lead is quite toxic, especially for children. So, I am considering applying Renaissance wax to seal the coin. The wax would seal the coin, at least theoretically, from the effects of moisture, and it would form a barrier of sorts that would allow safer handling of the coin. Is that advisable? How much will the wax alter the coin? The wax is also a polish. Would that cause the deposits, which I think add to the coin's appearance, to dissolve or darken? Thanks! The coin weighs 15.77 grams, and is 24 mm in diameter.
My very limited experience with Renwax is that it will darken the coin. I would imagine that the deposits would darken. I don't know how much compared to the rest of the coin but I think it would definitely alter the appearance. How often do you plan on handling the coin? I feel that random handling wouldn't increase the possibility of receiving a toxic amount of lead exposure. I'm no doctor/scientist though. If it were my coin, I would put it in a flip and call it good. I would also be sure to wash my hands after handling it. Other than that, I wouldn't mess with it. Other smarter people with be along shortly to probably destroy my opinions with facts
I do not know how to handle the lead portion of your question... hopefully someone will weigh in. In my experience the coin will have more of a "wet" look after you apply the wax and this would help bring out more detail - especially in the reverse of your coin. I think you would be happy with the results. The deposits will darken - which adds contrast. Also the wax can be removed if you do not like the results.
I would guess this is a core of a fourree. They would make planchets of silver coated base metal and strike them. Many such coins the silver fell off because not joined well. Yours is about perfect if you add 1.5-2 grams of silver. I would also guess it has lead in it, but is a mixture since lead is too heavy to copy silver.
Thanks. I did apply Renwax to the Cleopatra VII 80 drachma that I have been working on. Here are the "before" and "after" photos: Before Renwax: After Renwax: The coin is now a bit shinier, and the green deposits darker. The "Before" photo was taken in lower light conditions (should have used the flash).