I have a SLQ that is in very bad shape ( about a PO1 with pvc damage). It has no date on it and I read that vinager can restore the dates on coins. Would this damage the coin further?
Sometimes a smear of graphite lock lubricant powder can reveal a little of the date, but if the coin is as bad as described, probably not. Jim
Honestly, a coin in P01 condition won't stand any further value loss. I'd give the vinegar a shot and let us know how it turns out. You'll still have its bullion value, unless vinegar dissolves the whole darn thing, which I highly doubt.