Jufti knot needs an experienced eye to see because it is basically taking a set of two warps instead of one to knot across. I am almost sure that the Nains are Jufti knots because the use of this kind of knotting is prevalent in Nain. In terms of how fine it looks it will not look too different but it is less dense so it will not wear as well.
With all due respect to Little Persia I think they are both 6la Nain. They are quite fine and I think they are Habibians. As I said it is not the father that controls the weaving anymore and the quality is not the same as the Habibians that were being produced about 40 years ago.
Having just come back from Iran I can tell you the the price of these goods have rocketed there, so my valuation is based on what is available here in the shops and to some extend the pricing in Iran.
Your Isfehan is about $7500 and your Nains about $6000 each. I certainly would not be surprised to see them at about 20% higher price than this in some of the shops.
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