Persian carpet, compare with the other hand-made carpet in the countries of the world have a specialty with an overwhelmingly vivid colors. When we see the weaving techniques with our own eyes, we are very surprised, but the dyeing techniques, succeeded as a traditional techniques, is also making a great contribution for the making of beautiful carpet as jewels. In the recent excellent carpet, the cases are often found with a quite lot of color thread. Even if we had an excellent design, to produce a new carpet, innumerable color thread and excellent weaving techniques are required.
In the age when the chemical dye had not developed yet, the dyeing was performed in 100% by vegetation dyeing. Even after the chemical dye appeared, in the early stage, it was not used so much, because of poor quality and techniques and high cost which caused various troubles, for example color-fading. But later with the improvement of chemical technology the better quality and cheaper price was realized and obtainable, many dyers left apart from the vegetation dyeing. The vegetation dyeing is risky because of its instability depending on the dyer's delicacy, and further it becomes very hard to obtain the materials, also the cost increasing. Of course, even now, there are a few makers or ateliers who still sticks vegetation dyeing. For example at the Mohammad Jamshidi atelier, which is called "the king of silk carpet", they perform vegetation dyeing in 100% by themselves. Though the vegetation dyeing of silk thread is said to be much more difficult compare with that of wool, they have plenty of stock of color thread now as the result of 40 years continuous study with try and error. The atelier master Mr.Jamshidi Pool himself is performing dyeing process and the dyeing method is "Top Secret" and never come out.
For your reference, the current chemical dye is developed and improved specially for the carpet making, and it's very excellent for fastness and coloring, so nearly no trouble will happen.