This object was such a mystery we didn't know which collections manager to take it to! We started with mammals but meanwhile threw it open to our Facebook fans. Here's what some of them had to say :

'Looks like a petrified piece of sushi'

'Kangaroo Poo? Dingo Bollocks? '

'Looks like the underside of two or three barnacles'

'seed pod'

'bone or shell? or perhaps coral?'

Some interesting thoughts! Meanwhile the object was doing the rounds with our scientists- Marine Invertebrates, Malacology, Paleontology, Ornithology, Ichthyology each just as mystified as the the previous one!

Finally it was taken to our geo-scientists who performed  X Ray Defraction testing! They found out that it is made up of hydroxylapatite . Up to 50% of bone consists of a modified form of the inorganic mineral hydroxylapatite so we believe the object to be an altered bony structure. Unfortunately we cannot tell from what animal it comes from as it is unrecognizable so this mystery of the week remains a true mystery!