Originally Posted by
SharpMan
I can't be certain of course, but I have seen so many(thousands) natural stones
and I always pay attention to their looks and what mine and strata they are from.
OP says the stone is very hard, so very likely from a deep strata. It does not
look like suita at all, so probably tomae, namito or aisa strata. Looking at the
colour of the stone I see this greenish colour, and tiny hints of karasu
which makes me think namito the most and maybe aisa. And I get a ''namito
feeling'' looking at the stone. Might be aisa or between both.
Sharpman