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Nanocosmetics Used Since Ancient Egypt
Roland Piquepaille writes "French researchers have found that Egyptians, Greek and Romans were using nanotechnology to dye their hair several thousands years ago. Nanowerk Spotlight reports they were using lead compounds which generated lead sulfide (PbS) nanocrystals with a diameter of only 5 nanometers. At a moment where many people wonder if the use of nanoparticles is safe, it's good to know that nanotechnology has been widely used for a very long time."
This is another Roland Piquepaille article.
... their life spans were totally almost half of ours.
The people who wore these hair dyes were typically of the upper classes. The upper classes might well live to something even we would recognize as an advanced age.
Pepi II is thought to have ruled for 94 years. Ramses II lived to see his 90th birthday and his heir was in his 60s when he took the throne, ruling for about another 20 years.
Do not confuse life expectency with ages that might well be fairly commonly attainable. A huge chunk of the the lower life expectency is due to high infant mortality and death during childbirth, scewing the statistics. If one made it to the 21st year; and didn't work on pyramids and such, one's life outlook was held to be something around the classic age of man; four score and ten. That's why it's the classic age.
KFG