Isfahan is the former capital of Persia (Iran). They have a high reputation and may resemble nain rugs.
The colours in the pattern are clear and appear more due to the silk element.
The material used besides silk is kurk wool, which is a fine wool taken from the neck and back of the head of the sheep. This makes the rug very soft and glossy. Look out for Isfahan rugs that are signed by master weavers such as Enteshari and Seirafian, exclusive and well worth their price