This is both fascinating and an excellent way to show the "big picture" but also allow people to drill into the details.
There are other quartz mines that can produce the purity needed for the crucibles
agree, firing ion beams to make the mirror perfect one molecule at a time(they are declared the most precise mirrors on earth). This stuff is beyond wild. Not that I believe this stuff came from alien technology but if anything could be said to have not originated on earth this would be a strong candidate. And barely a hundred years ago we just figuring out flight at kitty hawk and now you have technology like this, its really amazing.
Everyone loves the electron beam etching. But no one asks how they know where to etch, which is what the most expensive machines do, I.e. mirror surface metrology. It's surprisingly hard to "just measure" the shape and roughness of these things
And that ASML is majority owned by Carl Zeis, a German company.
If anything it's the other way round. Asml owns 25% of Zeiss SMT. Source: I work there
Not really. A block of glass arrives at our facility. It undergoes a shitton of processing steps (much longer than you'd think) with atomic-precision measurements between the steps. All of the high end tools are self-developed and self-built. The mirror at the end does not have much in common with the block of glass at the start.