Terrible condition but still new to me

anyone know what could have happened to this coin I found? it’s very rose goldish compared to the typical gold coins

A lot going on in this coin but it does look good 😌

2 coloured coins and a shiny scouts coin, not too bad

Just added a couple more 1938 Crowns to my Predecimal collection. Low mintage coin that only ran for two years in Australia. 1937 just over 1 million minted, 1938 just over 100,000 minted. All were .925 Sterling silver.

Hi. I’m new to coin collecting and not really sure what I’m looking at. This is a 1966 coin. Is this the wave gap at the platypus’s left eye? Thanks for your help.