Police are searching for the thief that stole a rare 19th-century gold seal from an exhibit in Sydney’s west yesterday.

Explorer John Oxley’s fob seal was taken from its exhibition case where it was being displayed at Old Government House in Parramatta.

John Oxley was appointed the Surveyor-General of New South Wales from 1812.

The seal, made of engraved rock crystal and 18-carat gold, bears the family crest and is engraved with the motto ‘Patientia et Fortitudine’ or ‘Patience and Strength’.

The man police are searching for has a dark complexion, is about 175cm tall and of medium build.

He was seen wearing a black beanie, a dark top with a white stripe and carrying a small black backpack.

Detective Acting Inspector Sean Heagney told Ray Hadley there is no CCTV in the heritage-listed building.

“We’re definitely after the assistance of the public in relation to this one.”

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