The process is more complex and the energy more intense the more 9’s you need, because the contaminates in quartz are different depending on where it was mined. This complexity is why there’s only one place in the world that can do it at solar panel demand scale — and that’s because China dumped a ton of money into the process and doesn’t have strict pollution laws. If you can start with purer quartz, you’re way ahead of reaching scalable refinement.
So I'm wondering how much the initial ore purity really matters.