Just for info, I'm living in Imperia and I can assure you that there are not stones quarry here around.
As you can see stones are shipped from US, I suppose that Imperia LaRoccia is just a marketing name and stones probably comes from Taiwan.
Anyway, I don't own this stone and I can't talk about his performance, but I've read some post above that vendor says that comes from my area, well, isn't true.