Question about Rolex sapphire crystals...

[Meyrin]

Just wondering…

1) Does Rolex make its sapphire crystals in-house or do they have an outside supplier? If so, is it in Switzerland?

2) Are Rolex sapphire crystals higher quality than crystals on other watches? Can the quality of sapphire crystals vary from watch manufacturer to watch manufacturer?

I know that Rolex has its own gold foundry, so I think they might even make their own crystals. I´ve googled for answers but haven´t found any. Thanks in advance!