1943A is one of the highest mintages. Not much wear, but the zinc is starting to corrode (white residue). You can probably find one like this in a dealer's pick box at coin shows for around $0.50 - $1 retail.
Zinc coins are always problematic. Is there anything that can be done to improve the appearance of this coin?
If the white residue is due to a reaction between the zinc in the coin and the environment (oxygen, moisture, sulfur, etc.) then there probably isn't much you can do except physically remove it. Maybe use a soft brush. Where are the Metallurgists when you need them?
Zinc is very difficult to deal with - it is very reactive so any acid will dissolve the coin quite quickly. The discolouration is reacted metal - oxides and sulfides of Zinc mostly. Anything that removes these will also remove the metal underneath. Best left alone I think - they are very common in this condition and almost unheard of in anything better.
Yeah, silver dip removes the tarnish through dissolving the silver sulfide and converting it to metallic silver and H2S (phew). Wonder if anything could do anything for zinc sulfide/oxide.
