ancient Egyptians have been recorded to have been using colour for cures and ailments.They worshipped the sun, knowing that without light there can be no life. They looked at nature and copied it in many aspects of their lives. The floors of their temples were often green - as the grass which then grew alongside their river, the Nile. Blue was a very important colour to the Egyptians too; the colour of the sky. They built temples for healing and used gems (crystals) through which the sunlight shone. They would have different rooms for different colours. We could perhaps relate our present methods of colour/light therapy to this ancient practice.
There are lists on papyrus dating back to 1550 BC of colour "cures".
Their deep knowledge and understanding of the healing powers of the colour rays was so nearly lost when, later on in history, the Greeks considered colour only as a science. Hippocrates, amongst others, abandoned the metaphysical side of colour, concentrating only on the scientific aspect. Fortunately, despite this, the knowledge and philosophy of colour was handed down through the ages by a few.
The Chinese also apparently practiced Colour Healing. The Nei/ching, 2000 years old, records colour diagnoses.