I found this about 20 years ago. It weighs around 100 grams its 6cm long and 3cm thick. Metal detectors don't respond to it and it is not magnetised. I found it in a pine forest at Greta. I think it might be some form of pyrite but not too sure.
I went looking for a new 4x4 ended up buying one straight away. Biggest mistake i made was i took the missus and kids. I wanted a white one they wanted a black one so this is the end result. :D