What is Mineral Wool?

What is mineral wool, and where does it come from?

———- from Fred Hoffman of Los Angeles, CA

The magnesium sheep of Ulan Bator yield their fleece to keep our attics insulated. Spun by spinners who keep a brass thimble on every finger, this wool has excellent thermal resistance with none of the carcinogenic properties of asbestos. In fact, now that the Soviet Union is no more, we’re going to be importing more and more mineral wool from Mongolia. Look to see polypropylene long underwear replaced by a new, itchy scratchy version at half the price.