Question: Determining how much to use when working with powders

From this post, Making a water-in-silicone serum, Nanette asks: How do you determine the correct percentages of powdered ingredients? 2% of powder A could weigh significantly more than 2% of Powder B.These kind of conundrums are the reason we weigh all our ingredients intead of using teaspoons or tablespoons. How much allantoin are we adding…