Tom,
The things on the beach are cuttlebone. It is the 'skeleton' of a cuttlefish - a type of squid. It is sold in pet stores as a dietary supplement for birds. If you gather a bunch of them up and mail them to me, I'll feed them to my birds (I'll even pay for shipping! - surface shipping of course.).
Do you plan to do any diving on the reefs while you are there? Also, northwest Australia has a pretty big pearl industry. A walk on the beach might be more profitable there...
Regards,
Art S.
Tom's beach finds
Tom's beach finds
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