The Coin / Medallion I found under an old house

The Mystery Coin
The other day I wrote about finding some interesting things under an old house (where the floorboards used to be) and said I would reveal what the coin I found was.
Well it is as follows:
Silver Medallion – May 12 1937 To Commemorate the Coronation of their Majesties – Western Australia
Unusual coin / medallion, but it is damaged from being in a high salt soil, but still came up good after cleaning.
Here is a better example of the same coin / medallion I just found on ebay




































































































