They are famtastic, and used prices on eBay moved them into my budget.
My most recent project was fencing about 5.5 acres in, about 500ft of the fence line was on a rock shelf. tposts have a hard time being drove by hand into boulders. I used a 1" x 18" bit to drill all but two of the posts on that side.
Patent link:
https://patents.justia.com/patent/20220332632
Relevant blurb from another article:
“The family of new glass compositions, which the team calls LionGlass, get their new powers by swapping the soda ash and limestone for either aluminium oxide or an iron compound. The silica content can vary from 40% to 90% by weight.”