The breaking wave

Smooth on the outside, but rough and bumpy on the middle.
Slightly off white,
String as black as a crow.
A breaking wave,
Trapped within a bone.
Handed to me
When I was only young.
As delicate as glass.
If someone were to drop a brick on it,
It would become one million of itself.
From New Zealand,
Brought to Australia and given to me.
From a secret animal that no-one knows.
Could have been a bird, a human
Or something else.
If I were the bone carving,
I would tell you were I came from.
I would say that I was the only one I could trust.
MY BONE CARVING