http://www.apple.com/iphone-7/specs/ Sapphire crystal lens cover, which this seems to NOT be.
As for TouchID, see this:
https://support.apple.com/en-us/HT204587
The technology within Touch ID is some of the most advanced hardware and software we've put in any device. The button is made from sapphire crystal—one of the clearest, hardest materials available. This protects the sensor and acts as a lens to precisely focus it on your finger.
That's their page talking about the core of what the technology is based on. Don't you try to lecture me about the fundamentals of reading, Peace. You've been around here long enough to know I'm no idiot and know what the hell I'm talking about. They even talked about it in the keynote where they launched TouchID. All the iPhones have used sapphire home buttons since then.
I accept your apology in advance.