IARC Cancer Review: Group 1 IMEMDT IARC Monographs on the Evaluation of Carcinogenic Risk of Chemicals to Man . 7 ,1987,p. 349.(World Health Organization, Internation Agency for Research on Cancer,Lyon, France.: ) (Single copies can be ordered from WHO Publications Centre U.S.A., 49 Sheridan Avenue, Albany, NY 12210) ; Human Sufficient Evidence IMEMDT    IARC Monographs on the Evaluation of Carcinogenic Risk of Chemicals to Man . 42 ,1987,p. 185.(World Health Organization, Internation Agency for Research on Cancer,Lyon, France.: ) (Single copies can be ordered from WHO Publications Centre U.S.A., 49 Sheridan Avenue, Albany, NY 12210) ; Reported in EPA Talc (CAS NO.14807-96-6) Inventory.

ACGIH TLV: Human Carcinogen; TWA >2 mg/m³, Respirable Dust

The Talc, with the CAS registry number 14807-96-6, is also known as Cosmetic talc; Magnesium silicate talc. It belongs to the product inorganic chemical industry. Its EINECS number is 238-877-9. What's more, its systematic name is Talc. And it is finely powdered native hydrous magnesium silicate. It is used as a dusting powder, either alone or with starch or boric acid, for medicinal and toilet preparations. It is also an excipient and filler for pills, tablets, and for dusting tablet molds. The Talc may cause damage to health. It is Harmful by inhalation, Irritating to the respiratory system. Whenever you will contact it, please wear suitable protective clothing.

Preparation of Talc: Talc is found chiefly in the metamorphic rocks, often those of a more basic type because of the alteration of the minerals mentioned above. Talc is primarily formed via hydration and carbonation of serpentine, via the following reaction,
2Mg₃Si₂O₅(OH)₄ + 3CO₂ → Mg₃Si₄O₁₀(OH)₂ + 3 MgCO₃ + 3 H₂O 
Talc can also be made via a reaction between dolomite and silica, which is typical of skarnification of dolomites via silica-flooding in contact metamorphic aureoles,
3CaMg(CO₃)₂ + 4 SiO₂ + H₂O → Mg₃Si₄O₁₀(OH)₂ + 3 CaCO₃ + 3 CO₂

You can still convert the following datas into molecular structure:
(1)InChI:InChI=1S/3Mg.2HO3Si.2O3Si/c;;;4*1-4(2)3/h;;;2*1H;;/q3*+2;2*-1;2*-2;
(2)InChIKey:InChIKey=KNXVOGGZOFOROK-UHFFFAOYSA-N;
(3)Smiles:[Si](O)(=O)[O-].[Si]([O-])(O)=O.[Si](=O)([O-])[O-].[Si](=O)([O-])[O-].[Mg+2].[Mg+2].[Mg+2];