I'm taking an over the counter medication that has talc in it. Is talc a harmless substance?

Answer:
Talc is (Magnesium Silicate Hydroxide)

Crystallization is one of the oldest unit operations in the portfolio of separation techniques used for industrial and laboratory processes. Crystallization is used to achieve several functions: separation, purification, concentration, solidification, and the production of a crystal that can be used to determine molecular structure. Because the heat of crystallization is typically much lower than the heat of vaporization, considerable energy savings can be realized in applications where crystallization is an effective means of separation.

Solutes can be recovered from solutions by reducing the solubility through cooling, heating, evaporation, chemical reaction, or by adding a nonsolvent to the mixture. Alternatively, separation of a chemical species from a mixture of similar compounds may be achieved by melt crystallization. In such operations, the mixture is cooled and the species allowed to solidify differentially according to their melting points. Melt crystallization is an important means of separating para-xylene from ortho-and meta-xylene. An example of the purification of a chemical species is the manufacture of L-isoleucine, in which the material crystallized from a fermentation broth that has been filtered and subjected to ion exchange may contain undesirable impurities. The crystals are then redissolved and recrystallized to enhance purity. Concentration of a solution can be accomplished by crystallization of the solvent. For example, fruit juice is concentrated via the crystallization of ice.

It is also mainly used in making baby powder.

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