So, were there any canny guessers out there who worked it out?
The mystery object was a CODD BOTTLE OPENER. With so many visitors coming to Berowra, there were sure to be some of these bottle openers being used in the area.
The bottle opener fits over the neck of the bottle (codd bottles are also commonly known as ‘marble bottles’) and is pressed. This pops the marble into the bottle, allowing the drink to be poured.