hhbkiddo, as for the images of the first 50c coin posted on this thread, I cannot tell for sure if its real or fake. It looks real, and its not one of the replica coins sold on
ebay earlier this year. Having it in hand would help quite a bit in inspecting it. Finding fake 50c coins is tougher because you usually want a number of coins in various grades to develop an understanding for what is authentic. And to own 5 or more 50c coins from the period for each date becomes an expensive proposition. The only folks that handle enough volumes of these coins are the certification services.
But, there is now a new (at least new to me) problem of fakes on the market. If you own gold bullion coins or are considering buying some, then this may interest you:
http://www.tungsten-alloy.com/en/alloy11.htmApparently("rumor" only), some LGD bars sent from the London OTC market to Hong Kong were discovered to be filled with tungsten. This is bad because if true, then the Bank of England and/or HSBC will have some interesting explaining to do. Also, seems some other countries are double checking their LGD bars as a result. And checking for tungsten is not easy from what I have read so far...