platinum ring hallmark

Hi

My wife was was recently left a ring which we a local jeweller has
advised is diamonds set in what looks like platinum, but has a foreign
looking Hallmark (ie non-UK). Unfortunately we don't know and can't
find out where or when the ring was originally purchased.

The hallmark is on the inside back of the ring and reads Pt1000
[symbol] 016

Picture at www.nkwayne.co.uk/hallmark.jpg

As far as I can make out from reading on 'net the Pt1000 means pure
100% platinum, and the 016 probably refers to the weight (16gms - would
that be right?) but I don't know where to look up what the symbol in
the middle means.

Can anyone help?