1st chakra - The ROOT Primary color is red, other colors associated with the Root Chakra are black brown, and gray. The Naval Primary color is orange, others are all various shades of orange. Gemstones like Carnelian, orange Zincite 3rd chakra - The Solar Plexus Primary color is yellow, others are various shades of yellow. Gemstones like Citrine , Yellow Sapphire 4th chakra - The Heart Primary color is green and shades of green, the secondary color is pink. Gemstones like Rose Quartz or Green Tourmaline 5th chakra - The Throat Primary color is light blue like aqua or turquoise, secondary colors are various shades of lighter blues.
Primary color is dark blue or various shades of dark blue.
Now having said all of that, you must remember that each kind of crystal and mineral can and does have other transformational properties that are specific to that crystal or mineral. When you want to acquire more in depth knowledge about these properties, buy or check out one or more of the many books that cover this subject. But in the meantime you now have enough information to make a reasonably good pick by using the associated color method. It has been shown through Kerlian photography that the aura or energy fields surrounding objects extend a considerable distance from its core. It becomes a matter of personal taste and pocket-book after the right kind of crystal is picked.