Recipe for Roman cosmetic revealed.

Last year, while excavating a 2,000-year-old Roman temple in London, archaeologists discovered a small tin canister filled with white cream. In the Nov. 4 Nature, chemists who have examined the cream conclude that it is an ancient cosmetic face cream.

Analyses of the white material disclosed its ingredients: animal fat, starch, and tin oxide. The animal fat probably came from a cow or a sheep, the starch would have come from boiled roots or grains, and the tin oxide would have come from heated tin, says Richard Evershed of the University of Bristol in England. Because 15 percent of the cream was tin oxide and the interior of the canister showed no sign of deterioration, he and his colleagues inferred that the tin oxide served as a white pigment to make the skin look more fair.

Although archaeologists have found similar canisters before, this is the first to be intact and covered by a lid. The oily cream is well preserved and devoid of contaminants, say the researchers.

They note that the presence of tin oxide was unusual because Roman cosmetic creams typically contained lead acetate. By the second century A.D., however, the Romans were aware of lead's toxicity. That might explain the switch to an inert material such as tin oxide, says Evershed.

With the ancient face-cream recipe in hand, the researchers synthesized their own knockoff using beef drippings and cornflower from a local supermarket, plus tin oxide from a chemical company. The cream had "a greasy feel ... that gave way to a smooth, powdery texture," says Evershed.--A.G.