What did wealthy Romans smell like? In 2019, a resident of the Spanish town of Carmona was digging a swimming pool when they broke through into an underground chamber. Archaeologists from Seville were called to investigate and, climbing into the hole, found an intact Roman family tomb from the 1st century AD with six burial urns still in place. Among the funerary offerings to a woman who died around the age of 40 was a delicate bottle carved from quartz crystal, sealed with a bitumen stopper and with its congealed contents preserved inside. Using state-of-the-art scanning techniques like X-ray diffraction, dispersion X-ray spectroscopy, and scanning electron microscopy, experts were able to determine the exact composition of the substance inside the vessel without opening it. That the bottle would contain scented oil - a common offering in Roman graves - was not in itself a surprise but the precise essence was of great interest. Analysis revealed the perfume was made of two ingredients: firstly, a base or binder of olive oil which would help facilitate the application and preservation of the aroma. As for the essence, it was identified as pogostemon cablin, otherwise known as patchouli. Almost certainly imported from India, patchouli would have been a rare and expensive commodity in the Roman era and - along with its valuable vessel - attests to the high social status of the deceased. Researchers have previously detected hints of floral extracts in bottles used to keep cosmetics, known as unguentaria, but this is the first time the source of an aroma has been identified.