The Lydian Lion is considered to be the world's first (metal) coin.
Though stone and clay seals with pictorial designs pre-dated metal coins, the idea of designs were used to designate "by whose authority" the piece had value.
This coin was made of gold and silver alloy. It was minted by King Alyattes in Sardis, Lydia, Asia Minor (present day Turkey) c. 610-600 B.C.
What interests me most about these coins is that it is a material called electrum.
The pyramidions (capstones of the pyramids) were various stones which had been covered with metals (gold, silver,copper) and were called electrum.
Electrum is a conductor of electricity.
I am thinking that these civilizations may have been more advanced than what we give them credit for. In placing these electrical conductors high at the top of the pyramids, did they indeed have a way of generating electrical lighting?