Talc is a mineral known for
its softness and smoothness, often used in various industrial applications and
cosmetics. Here are some details about talc, including its Chemical Abstracts
Service (CAS) number:
1. Chemical Composition: The chemical formula for talc is Mg3Si4O10(OH)2, indicating that it is primarily composed of magnesium (Mg), silicon (Si), oxygen (O), and hydrogen (H). It belongs to the phyllosilicate group of minerals, characterized by sheets of interconnected silicon-oxygen tetrahedra.
2. CAS Number: The CAS
number for talc is 14807-96-6.
3. Physical Properties:
- Color: Talc can range in color from white
to gray, green, or brown, depending on its impurities.
- Hardness: Talc has a Mohs hardness of 1,
making it one of the softest minerals known. It can be easily scratched with a
fingernail and is often used as the standard for the lowest degree of hardness
on the Mohs scale.
- Luster: Talc has a greasy or pearly luster
when broken into thin sheets.
- Cleavage: Talc exhibits perfect basal
cleavage, meaning it breaks along flat, parallel planes perpendicular to the
direction of its sheets.
- Feel: Talc has a soapy or slippery feel
due to its softness and lubricating properties.
4. Formation: Talc forms through the alteration of magnesium-rich rocks such as serpentine, dunite, and peridotite, typically in low-temperature hydrothermal environments or through metamorphism of magnesium-rich sediments.
5. Uses:
- Industrial Applications: Talc is widely
used in various industrial applications, including as a lubricant, filler, and
coating agent in plastics, rubber, ceramics, paints, paper, and roofing
materials. It is valued for its ability to improve the performance and
processing characteristics of these materials.
- Cosmetics: Talc is a common ingredient in
cosmetics and personal care products such as baby powder, body powders, face
powders, and makeup products. It is used for its absorbent and softening
properties, helping to reduce friction and absorb moisture.
- Pharmaceuticals: Talc is used in
pharmaceuticals as an inactive ingredient in tablets and as a lubricant in the
production of oral medications.
6. Health and Safety: Talc is generally considered safe for external use in cosmetics and personal care products when properly formulated and applied. However, concerns have been raised about potential health risks associated with inhalation of talc dust, particularly with long-term occupational exposure, as it may be associated with respiratory issues and lung cancer.
Overall, talc is a versatile mineral with a wide range of industrial and cosmetic applications, prized for its softness, lubricating properties, and chemical inertness.
If you need further information or have specific questions, feel free to ask!