I know that I can't correct any current pitting, but is there anything that can be done to 1. remove some of the white haziness??? 2. preserve the current state to eliminate further pitting?? I have heard mention of using WD40, but not sure of the source of that information, and would like further advice before I do anything.
Zinc naturally deteriorates in the atmosphere - it's the nature of the metal. As long as it is exposed to the air - that's what it will do. As for the use of WD-40 - can't say as I know for sure but it may remove the oxidation. But it will return in time. About the only way to stop it is to seal the coin and not allow any air to come in contact with the surface. This next part is anathema to me but it may present a solution to your problem. In the old days many collectors would seal their coins with shelac or clear fingernail polish in order to stop the effects of oxidation or toning. But with zinc - any of the whitish oxidation must first be removed. It does work. But any numimsmatic value the coin may have will be gone forever. Sorry I can't be of more help but that's about all I know.
Doug, I'm not so sure that sealing those coins in clear fingernail polish will destroy their numismatic value. Acetone, which is the main ingredient in many fingernail polish removers, will completely desolve fingernail polish, and is harmless to metal. (Wouldn't recommend it for copper, though) I can't say for sure that this is a good idea, but it might be worth trying.
Try using KoinSolv, then place the coins in a safe holder such as Eagle or AirTight. The use of a Silica dehumidifying Gel or a product called metal safe, will help to prevent further damage. (they both are used to eliminate pollutants from toning coins.)
