Gents, I'm forthrightly looking to add to my rockpile for no compellingly good reason. I got HAD bad...

In any case....is there a natural stone you could recommend that would be a 'transition' between an aoto and a super-fly jnat finisher? Or between an 8k shapton and said finisher?

I note a lot of people go from 8k to 12 or 16k to a finisher. Is there a 'natural' equivalent to that synthetic 12-16k transition stone?