WELL, had lots of fun with water, string and scales, so the result was as follows: tested 4 sovs including the 1985 coin , used 4 different weight types ( my scales has settings for oz, ct, gn and g.) all coins weighed the same in all ranges. All coins weiged the same in the sg test , dry weight divided by weight in water, gave me a final reading of 20.43. I know from the article on sg that 24 ct should be 19.3 ( there was no 22 ct rating, 9, 14 18 24 but no 22, strange for a forum on sovs , go figure). My result of 20.43 is higher than the 24ct rating of 19.3, I'm putting this down to the tread I was using, had to double it up to "lasoo" the coin but either way all four coins returned the same result. note. it appears the aussie sov is slightly smaller that the English sov , 21.5mm as opposed to 22.05 approx , checked it out on the web and this confirmed that it was correct. So I think I will hold on to this sov, even if it is a jewellers copy, has past all tests to date, must be 22ct gold and if nothing else I've a coin that's rare, even if it is not the real deal. Thanks all.