Use to set mineral after makeup has been applied. Use to hydrate skin at any time - especially in dry climates or planes. Oily skins can use as a moisturizer. Laser patients spritz frequently - especially during dry, flaky period. D2O is Deuterium Oxide - heavy water. Its hydrogen molecule is twice the weight of the molecule in ordinary water, which makes D2O 10% heavier than H2O. Research has found that: Heavy Water has a higher resistance to vaporization, which helps it stay on the skin for longer periods of time. It has more viscosity. This thickness gives it a higher plumping effect than regular water and the skin does not dry out as quickly or as deeply. It requires ten times as much energy to be ionized than regular water, which makes it more protective against ultra violet radiation. It inactivates certain acne bacteria, making it an ideal moisturizing agent for blemish-prone skin. Note: It's not a good idea to spray spring water on the face, because most spring waters contain chalk, and that leaves on the skin a white film which is hard to remove. Directions For Use: Spritz to hydrate skin and to set mineral powders.