YOUNG Joseph was an exemplary youngster and he loved his grandparents and did their bidding.
But one day this trust took a disastrous turn.
He had been told to collect some stones from the nearby wara to help make a mumu.
Now, if you don 't know, the mumu is are prepared in a pit with the first ingredient being red-hot stones. But not just any stones - they have to be mumu stones.
Then you pile on banana leaves, meat, vegetables, herbs, coconut milk, more leaves - and cover the whole thing and leave it for a few hours.
But there's an important difference between Igneous stones and the sedimentary variety. Igneous are generally volcanic and have no threads or fissures, as they have been melted hard into one solid block.
Sedimentary stones, on the other hand, are riddled with lines and cavities which can absorb water.
How to tell the difference?
Well Joseph went down to the river to collect some stones for the mumu. He chose the best ones he could see and took them back home.
Unfortunately they were sedimentary.
The mumu was cooking, steam was issuing and the family was gathered for the feast.
Suddenly there was a great bang and a whoosh, and all the relatives were covered with a green smear of vegies, meat and gravy.
Luckily no one was hurt.
Joseph had learned his lesson - don't trust a rock by i's colour.
A sedimentary stone can look like an igneous. But the steam will boil and an explosion will result.
Don't mix your rocks.