Posted 04/20/2012 9:07 pm
Hello and welcome. Hope we can help. 
First off, it's definitely not a "mule" as described by the seller. It could be a "grease-filled die", but it could also have been polished to death by a jewellery polisher. I can't tell from the pics.
There's a fairly simple test you could try to tell the difference. Weigh it, and compare the weight to a perfectly normal 20p coin. A normal coin should weigh exactly 5 grams, and a grease-filled die error should weigh exactly the same. If it's a fake error (post-mint polished), to make the coin look like that it would have to lose so much metal it would make the coin weigh substantially less than 5 grams.
First off, it's definitely not a "mule" as described by the seller. It could be a "grease-filled die", but it could also have been polished to death by a jewellery polisher. I can't tell from the pics.
There's a fairly simple test you could try to tell the difference. Weigh it, and compare the weight to a perfectly normal 20p coin. A normal coin should weigh exactly 5 grams, and a grease-filled die error should weigh exactly the same. If it's a fake error (post-mint polished), to make the coin look like that it would have to lose so much metal it would make the coin weigh substantially less than 5 grams.
Don't say "infinitely" when you mean "very"; otherwise, you'll have no word left when you want to talk about something really infinite. - C. S. Lewis
