Mint Essential Oil is colourless or of a very pale yellow. The smell has an agreeable freshness, strong, penetrating, giving that feeling of being able to breathe deeply. Fresh, the oil is very fluid, but it thickens and darkens as it ages. Mint is good for the nervous system, acting as a regulator and sedative; menthol is well known as a cardiac tonic in pharmaceutical preparations. It is a good blood cleanser, because it is antiseptic and antibacterial.