An important large quartz/silicon dioxide mining complex in the Appalachians’, but definitely not the only source in the world:
https://www.tandfonline.com/doi/full/10.1080/08120099.2024.2362296#d1e2010
https://www.wired.com/story/book-excerpt-science-of-ultra-pure-silicon/
https://waferpro.com/fused-silica-wafer-vs-fused-quartz-wafer/
“An important large quartz/silicon dioxide mining complex in the Appalachians’, but definitely not the only source in the world”
I doubt there’s a critical element or material that the United State, and only the United States, controls. But there are PLENTY that the US does not have, or at least the Leftists running the US won’t allow us to access.
So we need to look at these types of articles with a bit of skepticism.
At present, the main suppliers of HPQ globally are the United States of America, Canada, Norway, Brazil, Russia and India (Pan et al., Citation2022).
https://www.tandfonline.com/doi/full/10.1080/08120099.2024.2362296#d1e193
The United States of America hosts the world’s largest HPQ deposit, Spruce Pine, North Carolina, which has been mined mainly for feldspar and mica for over a century (Swanson & Veal, Citation2010). The Spruce Pine pegmatite complex is approximately 40 km long and 16 km wide (Brobst, Citation1962). HPQ from Spruce Pine is associated with near-source anatectic pegmatites that locally intrude surrounding host rock and granodiorite plutons (Swanson & Veal, Citation2010).
https://www.tandfonline.com/doi/full/10.1080/08120099.2024.2362296#d1e2010