Egyptian mummies have fascinated the public for centuries. But until recently, researchers had only identified two ancient documents detailing the embalming process. Now, reports Amanda Kooser for CNET, a newly discovered, 3,500-year-old manual may shed more light on mummification’s mysteries.

Per a statement, Sofie Schiødt, an Egyptologist at the University of Copenhagen, uncovered the guide while translating a portion of the Papyrus Louvre-Carlsberg for her doctoral thesis. The nearly 20-foot-long manuscript, which focuses mainly on herbal medicine and skin conditions, contains a short section outlining embalming methods, including how to preserve a dead person’s face.

“The text reads like a memory aid, so the intended readers must have been specialists who needed to be reminded of these details, such as unguent recipes and uses of various types of bandages,” says Schiødt in the statement. “Some of the simpler processes, [for example] the drying of the body with natron, have been omitted from the text.”

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