Makeup Tips
Good mineral makeup will be totally free of preservatives and filler ingredients. There's nothing in it except pigments and various mineral agents that smooth and protect skin from sun damage, which is why mineral makeup is so much better for your skin than drugstore and even fancy department store brands. Some people worry that the lack of preservatives in mineral makeup means that it can somehow "expire" or go bad rapidly, but actually it's just the opposite.
Mineral makeup is inorganic and contains no moisture, therefore bacteria cannot form and thrive, which is why no preservatives are needed to stabilize high-quality mineral products. Furthermore, these products will not spoil because they contain no fillers or synthetic dyes. So in theory, mineral makeup will last forever.
However, it is possible for you to transmit organic material to the makeup if you allow a brush to contact the makeup after the brush has been on your face. Try to avoid dipping used makeup brushes directly into your main container of mineral makeup. A good alternative is to pour some out for application onto a clean, washable surface or into a little bowl another is to use a washable, self-dispensing Kabuki Brush for applying your foundation.
As a rule of thumb, you should toss any cosmetics when they take on an unattractive change in their color, texture or odor.
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makeup tips and general mineral makeup info.