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You can stream thousands of documentaries and nonfiction TV shows at CuriosityStream.com/SciShow. Picture this: It’s 1400 BCE in Egypt, and you’re dead.

But don’t worry – you’re prepared for this. Your people have preserved your body, bathing it in scented balms and perfumes to make sure you can go right on using it. All you’ve got to do is have a quick little chat with the judge of the dead to see if your heart measures up, and you’re on your way to the afterlife.

Thousands of years later, there’s a shocking amount we know about this ancient Egyptian  journey to immortality. But there's one critical thing we don't: the recipe for the perfumes and embalming fluids that helped preserve their bodies for so long. Modern chemistry is gradually unlocking these ancient secrets.

And the scent of immortality is just one of the things those old perfumes are hiding. [intro music] The ancient Egyptians had what archaeologists call a sophisticated funerary culture. It’s less that they were obsessed with death, and more that they thought life was pretty awesome and expected more of the same in the hereafter. They wrote down a lot of what they did to make sure that would happen.

But… not all of it. We know that they used complex mixtures to embalm bodies and organs, but not what those mixtures were made of. What materials did they choose, and why?

Where did they get them? And what does that tell us about the lives of those people so long ago? Fortunately, we have access to tons of this stuff in the archeological record.

The canopic jars used to preserve mummified organs, sarcophagi, and even mummies themselves all contain traces of embalming material. Let’s consider the mystery of Kha and Merit. These were a husband and wife buried together some time after 1400 BCE.

Kha was an architect who served under three different Pharaohs, and seems to have been held in high regard. Which makes it weird that the mummification of these bodies seems… sloppy. Merit’s skeleton is in awful shape, and neither of them had their organs removed.

Usually what we see in mummification, at least for royal mummies, is that the heart will be preserved and put back in the body, certain organs will be embalmed and preserved in canopic jars, and the brain will be tossed out because… who needs that… But none of this was done with Kha and Merit, leading some to propose that they were never mummified at all, just wrapped in linen. However, in a 2015 study, researchers challenged that view… with perfume. Or more specifically, with chemical analysis of the embalming agents present in Kha and Merit’s mummies.

The technique they used is called gas chromatography-mass spectrometry Or GC-MS, and this is a real favorite among chemists. It’s a form of chromatography, a fancy word for separating out a mixture of chemicals. If you’ve ever done that experiment as a kid and watch as water separates the components of the ink, you’ve done chromatography, congratulations.

By forcing the components of a mixture to travel at different speeds, you separate them so you can identify them one at a time. In GC-MS, the sample is vaporized and sent through a long, skinny tunnel to separate the components. Each molecule is then broken up into fragments, each of which has a distinct size and charge.

You can fit these together like a molecular puzzle to identify what molecule they started out as. In doing this, they found that Kha’s mummy contained an embalming agent consisting of a base of oil or fat, aromatic plant extract, conifer resin, and additional plant-based substances. Hey, they were analyzing 3,500-year-old mixtures here!

It’s usually not going to be possible to ID every ingredient down to the plant species, but you can at least get a rough idea. Merit’s recipe was similar but also contained beeswax and, bizarrely enough, fish oil. Not what I want in my fragrances, generally.

Her outer shroud also contained Pistacia resin. That’s a group of trees with several uses in fragrance, including mastic and terebinth. From this, the authors of the paper argued that Kha and Merit’s preparation for the afterlife wasn’t shoddy at all.

These were fancy, imported perfumes. And the state of their mummies, all things considered, wasn’t that bad. In fact, the researchers propose that the presence of coniferous resins went a long way in preserving their bodies, thanks to anti-decay chemicals found in pine trees.

Sure, they didn’t get the full  Pharaoh treatment, but who does? Then there’s Senetnay, a woman who lived around 1450 BCE – not long before Kha and Merit – and was a wet nurse to King Tut’s great-great-granddad. In a 2023 analysis of her canopic jars, researchers noticed something that shouldn’t have been there.

The team used GC-MS to identify the substances present, but they also used Liquid Chromatography with tandem mass spectrometry Or LC-MSMS. This is a type of chromatography done in liquid rather than gas form. But as the name suggests, you sort of double identify the stuff after it’s pulled apart.

You once again fragment the molecules into pieces with a certain mass and charge, but then you fragment the fragments. This gives a better and more specific signature, because all those little puzzle pieces can only fit together in certain ways. Senetnay’s mummification residues included beeswax, various oily substances, and resin from pine trees – which might have been larch or cedar.

They also contained the chemical signature of something that might have been a fancy ingredient called dammar. By fancy, I mean trees that produce  dammar grow in southeast Asia. We know that Egyptians used dammar much later on, by around 600 BCE.

But this finding would push back our knowledge of Egyptian trade links with southeast Asia by a good thousand years. We really don’t have any archeological  evidence for that kind of trade, though,   and the stuff they identified as dammar  could also have been Pistacia again. So they’re not rewriting  the history books just yet.

A museum in Denmark is actually using a recreated  version of Senetnay’s perfume as part of an exhibit. So if you want to know what immortality smells like, start researching flights to Copenhagen. Finally, we need to talk about Nestawedjat.

She died and was interred around 700 BCE, near the city of Thebes. In the 19th century , she and her three coffins were looted and eventually ended up at the British Museum. During her stay at the museum, it was incorrectly determined that Nestawedjat’s mummy didn’t belong with the coffins, and they were separated.

This effectively erased her identity – which, according to ancient Egyptian belief, was an important part of her  survival in the afterlife. In a study published in 2021, researchers used various chemical techniques to study Nestawedjat’s mummy as well as the three coffins they suspected might rightfully belong to her. They suspected this partly because, well, they’d come in together, plus there was a stain on the mummy’s shoulder that matched the innermost coffin.

Their techniques included, once again, GC-MS, but also one called Fourier-transform infrared spectroscopy This is a different strategy than chromatography. Rather than separating the sample, you look at the infrared light it absorbs. Then you do some math based on the light that isn't absorbed to get an ID.

The perfumes from the mummy and the coffins were a match,. The embalming material was made of beeswax and an oil or fat. Pine-type trees show up here too, with signatures that can be interpreted as juniper, cypress, and/or cedar.

The researchers repeated the claim that the pine-based substances had a preservative effect due to the presence of compounds called sesquiterpenoids. These compounds smell nice, which is obviously a good enough reason to put them in perfumes and balms. But they’re also shown to resist decay, and given their widespread use, it’s definitely possible that  Egyptian embalmers knew that.

In the end, the results clearly showed that Nestawedjat and her  coffins belonged together. Her name and identity have been restored, and thus, a part of her immortality. So now we know.

As you’re making that journey  through the underworld, you’re accompanied by the scent of pine trees: rare, imported ingredients that reflect the care your people took to make sure you had a nice afterlife. There’s really no match in history for the technology the ancient Egyptians developed around mummification. But the technology we have to unravel it, and reveal the stories of these four people, is pretty neat too.

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You might even see some familiar videos from Crash Course while you’re browsing. But since you watched this video, you’ll probably want to check out all of their documentaries on ancient Egypt, including the Tombs of Egypt. You can watch Egyptian scientists learn about forgotten mummies!

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