For natural dye/vegetable dye rugs, weavers usually impliment naturally found items to color the wool. These items vary from vegetables to beetles and other.

Firstly, it would be very surprising if this were a naturally dyed rug. These colors are just not typical of natural dyed wool. Sometimes sellers call a rug natural dye because just a small percentage of the dyes are natural, but real professionals and connoseuirs consider a rug vegetable dyed only if all colors are of vegetable or insect origin. In the case of this rug, we doubt it is truly a vegetable dyed rug.

Number 2, if this were an Antique Persian Isfahan (by US customs definition and in professional rug terminology, antique means 100+ years old), the rug should have less flourescent coloring and a softer overall color scheme. Perhaps this rug might be best termed semi antique (50 years old).

If you want to see a really fine Isfahan from the 1920's, take a look at this rug:
http://www.spongobongo.com/JBOC9990a.htm