Is that really Zini? The texture reminds me those special order dsq that eot often sell
clay composition looks a little off to me.
By no means am I any sort of an expert.
There were many versions, with different stamps. This is what Dr. Lu writes in his article on the Quin Yin series:
"In the 1970s, all the “Qing Yin” pots that we had studied are made of red clay (hong ni). Purple clay (zi ni) “Qing Yin” were made only from the 80s, and there are three base seals for this batch. One of them is similar to the 70s’ base seal, the other two seals are longer and narrower and can be divided into 22 or 23 character versions."
So I'd be guessing 90's repro? But very nice in any case.