When may minerals that occur naturally in nature also be used in nature-identical (synthetic) form?
Only in very rare cases do we find minerals under the form of pure crystals in nature. Often these minerals are stored together with other minerals and are therefore impure. However, cosmetics must meet very high purity requirements; in particular toxic heavy metals must be avoided. In the case of minerals this means that naturally occurring material must be dissolved so that the unwanted elements can be removed as far as possible and the pure mineral can then be extracted from the mineral solution.
