Talc is a mineral in clay mined from underground deposits. It’s the softest mineral known to man and that makes it useful in a wide range of consumer and industrial products. Asbestos is also found underground, and veins of it can often be found in talc deposits, leading to a risk of cross-contamination, geologists say.

Full article here: https://www.nytimes.com/2018/12/14/business/talc-asbestos-po...