The pot of ointment was still moist but smelled sulphurous

The sealed pot full of ointment, complete with finger marks, was discovered at a Roman temple complex in Southwark, south London.

The tin pot is about six centimetres wide and plainly decorated.

The substance was described as still wet but smelling "sulphurous".

Initial guesses of its function ranged from cosmetic face cream and toothpaste to something that was smeared on goats before they were killed.

The pot was found in a Roman drain and appears to have been deliberately hidden.

It was opened before the media at the Museum of London by museum conservator Liz Barham.

We've been asked several times what to expect in there, but I don't think we could have expected that it would be so full, or that it would be some kind of cosmetic, moisturising cream or whatever it is Gary Brown, managing director

As she opened it, a strong sulphurous smell was released.

Ms Barham said: "If this is a sealed Roman container, those are Roman finger marks."

The discovery was unearthed in July by Pre-Construct Archaeology, whose managing director, Gary Brown, looking over Ms Barham's shoulder, said: "I'm astounded.

"We've been asked several times what to expect in there, but I don't think we could have expected that it would be so full, or that it would be some kind of cosmetic, moisturising cream or whatever it is.

"Clearly, Roman creams of any type, paint or cosmetic, do not normally survive in the archaeological record, we don't know if it's unique, but it's pretty exceptional."

The excavation is in Southwark

Francis Grew, curator of the museum, said it was known that the Romans used asses' milk as a face cream.

The religious complex is the first in London and one of the most important ever seen in Britain.

The site is rare evidence of organised religion in London at the time and opens out a previously hidden district of the ancient city.

Two square Romano-Celtic temples have been found, with a possible guesthouse all contained within a precinct.

The small to medium-sized stone temple buildings date to around the mid-second-century AD.