Old Kingdom of Egypt
There is disputed archeological evidence of use of lenses in antiquity, spanning several millennia. It has been suggested that glass eye covers in hieroglyphs from the Old Kingdom of Egypt (c. 2686–2181 BC) were functional simple glass meniscus lenses. Similarly the so-called Nimrud lens, a rock crystal artifact dated to the 7th century BC, may have been used as a magnifying glass or may have been a decoration.