I know that Yixing is a bit tricky to identify but any opinion will be welcomed.
My personal opinion is that the pots are fake.
If they were by Gu Jingzhou as the marks state I would expect everything to be perfect. On one of the pots there is a piece of clay on the inside wall, the strain holes are a bit rough, the underside of the rims are a bit uneven... it just looks like the craftsmanship is not on a good level.
There is still clay residue inside which makes me think they were never cleaned and seasoned but they show some age signs. The lids fits snugly though. And that stains or whatever it is on the exteriors look like not being natural.
What do you think?
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Fake age signs, I'm sure. This was either made for export or the tourist trade, I would think. As far as I understand, no Chinese here would buy such items.
Sorry, but can not help with mark.