New uniform buttons
? 1960-90s: The kangaroo was less stylised and streamlined in earlier buttons. See http://www.austbuttonhistory.com/uniform-buttons-2/uniform-buttons/#Trans_Australian_Airways
Prince Alfred College
Many (if not all) of the school uniform buttons were made by S. Schlank and Co. Allan Olson was a former employee of this firm, and bought the former Schlank plant, equipment (including many old dies) and the factory located in Forrestville, South Australia after Schlank closed in 1969.
The backmark is almost off the button! This dates pre 1953.