Essence powder oxidizes and turns orange — how to choose shades that stay true?

Powder foundations oxidize, or turn a little orange, because iron oxides in them react with the oils on your skin, the pH of your skin, and things in the surroundings, like heat or humidity.

If you want to find a shade that stays true, test it on your chin instead of your wrist and look at it in natural light after a few hours. If it gets too dark, go one shade lighter.

Also, look for powders that don't have a lot of oil in them (matte or semi-matte), have antioxidants or stabilizers in them, and keep them out of the sun and away from moisture so the colors don't break down.