Nain Rugs come from the Central area of Iran and weaving of these types of rugs didn't even begin until the 1930s. The majority found in America, date back to after World War 2 and the best ones were made prior to the 1980s. The deisgn is normally floral with a central medallion on a a dark blue or ivory floral filled. Wool with ivory silk outlines can normally be found in the rug and the size is normally in the 6 foot by 9 foot range or smaller.
Note with silk in a rug the cleaning procedures must be specialized by a professional to ensure the silk is protected. Also any of the dark red and brown color in the rug could have a bleeding issue during cleaning. Should only be cleaned with the proper shampoos, drying procedures and a professional.
Recommendation: If you own one of these or think you might have a Nain, please take it to me or someone like me to ensure you don't ruin a fine piece of floor art. With three different types of fibers and the inherited cleaning issues that may arise, this is not a rug you want to take outside and wash yourself.
On a SIde Note: This is a rug that does well on the open market and crosses over between the lovers of wool rugs and silk rugs. If you don't own one, I would look for one the next time you are in the market and enjoy the natural beauty this rug has and tell your friends of how you own a silk rug.