They're our personal rainbows, located in the aura, an electromagnetic force field which surrounds each living thing. The energy of the aura is that of our thoughts, feelings, and spiritual essence. The chakras concentrate and coordinate the flow of these energies to and from the physical body. Each chakra governs a particular area of the body and the experiences associated with it, as described in the chart below. There are some variants on these relationships.
Some people believe that the first, or root chakra, is red and that the crown chakra is violet.
We, based on a different version, assign black, brown, and red to the first chakra, and white to the seventh. We like this system because it gives us places to put dark and white or clear stones. Systems may also assign different locations to the third chakra, some relating it to the navel, as we do, others to the solar plexus. We do include the solar plexus in our chart, as we consider it an important location for stone placement. To bring this chart into practical perspective, say that you want to develop more personal power.