Natron

Comes from the Ancient Egyptian word ntrj. This was a salt found in Egypt's Natron Valley. They used it in the mummification process to dry out the body (it also made it hard for bacteria to live by raising the pH levels). They also added it to castor oil to make lamp fuel that didn't create smoke, so that artists could paint inside tombs without getting soot stains on them. Plus, they used natron pellets ("smin" {singular}, I think) as funerary offerings for kings who had passed away. Finally, they used it to make a color known as Egyptian blue as well as faience, a particular blue ceramic glaze. Ancients (whether Egyptians or others; the article didn't say) also used natron to clean themselves and their home (it made a kind of soap when mixed with oil), dry and preserve meat, repel bugs, make leather, bleach clothes, increase "spiritual safety" (including that of the dead), to help solder together precious metals, and Romans (and others) used it as part of their glass-making processes.