There are few things to be considered when going for an identification of dyes used in a rug. You must always learn this by practically examining different types of rugs and their colors. With experience and correct knowledge, you will become an expert in examining dye types for rugs of all kind. Most people would feel satisfied by relying on books or other learned persons; however, you must always prioritize firsthand knowledge and your experience. With some effort you natural dyes will learn that dyes have immense variety. So, let's begin to count ways through which you can increase your knowledge about synthetic dyes.
Finding people with experience is a nice way to increase your knowledge. But, as you already know, experience should never be compromised. Ask yourself, that who could be the person spending maximum time with the rugs? Well, a rug dealer spends ample time with various rugs and he/she knows how to scoop out the best from others. The inventories that these rug dealers have may prove to be very beneficial for you. However, it is important that you bring diversity into your methods of learning. You may go to several dealers, instead of sticking to one or two. When you interact with several dealers, you will be viewing more types of rugs and your knowledge will expand too.
There are few places, where you can find tons of knowledge about rugs. One of these places is the rug conventions, including dealer fairs, sale previews etc. Such events give you an opportunity to view thousands of rugs at a single place. Moreover, on such occasions you also have the opportunity to discuss and ask questions about those rugs. There are several experts present in such occasions, who may guide you appropriately. You may add auction house staff, collectors, dealers etc in the list of your teachers.
Useful Things for New Learners!
You must remember that learning about rugs and their dyes can only be possible, if you get some practical experience with several types of rugs. You may find a common issue in rug industry, concerning the color blue (whether it's synthetic or natural). Now, the type of natural dye that is used for 'blue' shade is similar to other synthetic dyes, such as indigo. Indigo is a dye that has an interesting attribute; it doesn't colors whole yarn! Indigo shades only cover the surface of yarn; once, the surface peels off the original yarn shade come in view.
One thing that would definitely surprise you is about green dyes. Green natural dyes are most rare type. There are early Turkoman rug pieces that contain dark green color of natural dyes; however, most green shades that are being used nowadays in rug industry are synthetic. The brown and black dyes have been derived from sheep with wool, initially. You need to be a keen observer to know the difference between natural and synthetic black dyes. Now, another important thing natural dyes to keep in mind is that natural purple dyes are very rare to find. Red dyes are also very difficult to be distinguished from natural to synthetic shade because of diverse hues available. So, learning to distinguish natural and synthetic dyes is not a simple task, as many people may assume.