We may never know why the OP didn't trust the top tier grading companies assessment, but I'm sure there is a bit more to the story.
I have a Sigma Analytics Precious Metal Verifier - it can detect specific metals through slabs. You set the analysis to say, gold - .999 fine, it will give you a read-out within brackets if it is real. If the reading is outside the brackets, you most likely have a fake. I used it on three 1 oz. gold bars I bought - they were all fake and I got a full refund.
You didn't take side cutters and cut the coins in half to make sure they are solid gold through and through? Doesn't sound like you verified anything?
