And I hate to think what my camera and telescope lenses will look like, after they have been buried in the sand for a few millennia.
The Crystal Sun. (snip) contains some interesting information:
'Ancient lenses! Well, how far back do they go? The earliest actual lenses which I have located are crystal ones dating from the 4th Dynasty of Old Kingdom Egypt, circa 2500 BC. These are to be found in the Cairo Museum and two are in the Louvre in Paris. But archaeological evidence showing that they must have been around at least 700 years earlier has recently been excavated at Abydos in Upper Egypt. A tomb of a Pre-Dynastic king there has yielded an ivory knife handle bearing a microscopic carving which could only have been done under considerable magnification (and of course can only be seen with a strong magnifying glass today). Thus, we know that magnification technology was in use in Egypt in 3300 BC. I reproduce both photos and drawings of this crucial evidence...'
http://newdawnmagazine.com/Articles/Crystal_Sun.html
(The 'experts on Assyrian archeology' are probably members of TROP who would prefer any and every useful invention to be attributed to islam...)