Adding more zinc oxide powder will offer more coverage and adding less will create a thinner coverage that is better for highlighting. (wellnessmama.com)
I bought the recommend zinc oxide powder, but everything I have read states that it is super dangerous to work with in case of inhalation of the power and the non scented fumes it produces after being heated. (mommypotamus.com)
Natural Zinc Oxide Powder - Non Nano and Uncoated - Baby Safe, Cosmetic Grade Fine Powder - FREE: Recipe eBook (amazon.com)