Anatase didn’t exist in the 15th century??
I recall a nineties book about humanity’s use of salt.
It mentioned that Europe was eating salted cod for about century after European waters had run out.
There was also a mention of merchants writing an angry letter to Columbus decrying his claim to have discovered the New World when it had been under-the-radar knowledge among fishermen and whalers for decades.
The anatase question was raised by a lone researcher and map skeptic (iow, a true believer), I think he’s now deceased. Even at that time, in his specialty, he was nearly alone in his belief that anatase had never been made before recent times, which is not the same thing as thinking that it never been *purposefully* made, or *discovered*, or made with a modern knowledge of chemistry. :’)