1966 50c Black Amazing Black

Sorry Shane but these are simply Bullion coins in this condition and nobody really cares about them much numismatically
Probably just a streaky planchet not unlike many of our later penny's and half penny's.

Ahhhh comes the light, sel_69l. That might explain what happened to that black 20 cent coin I posted a couple of months ago.

Since then I have found a black and mottled 20 cent coin and thought it looked like it had been through a bush fire or something ... which it probably had if heat turns a coin black.

Making a silver coin black is even easier. No heat required. Just store it with something sulfurous - eggs, garlic, onions, rubber, that sort of thing. A few weeks to a few months ought to do it. Of course, heat plus sulfur makes it happen even quicker.

Sorry, shanew, but this isn't a "mint error" of any kind. It's just unusual toning. Of course, being "just toning" doesn't mean it's trash, or that you aren't allowed to like how it looks. I once acquired a 1927 Canberra florin from a bulk lot; it was in superb condition but the entire coin was toned a glossy jet-black. I asked a dealer what he thought it was worth and he said words to the effect of "That thing's ugly, I'd have to clean it before I sold it - it's worth only melt otherwise". But I liked it, so I decided to keep it as-is.