mineral wool

American  

noun

1. a woollike material for heat and sound insulation, made by blowing steam or air through molten slag or rock.

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mineral wool British  

noun

1. Also called: rock wool.  a fibrous material made by blowing steam or air through molten slag and used for packing and insulation

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Etymology

Origin of mineral wool

First recorded in 1880–85

Example Sentences

Common insulation materials include fibreglass, non-combustible mineral wool, foam boards and natural fibre such as wood or cork.

From BBC • Mar. 25, 2026

The angled roof is made out of a reflective, resin-coated metal and sits atop 9 inches of mineral wool insulation, which helps preserve the building’s interior temperatures and buffer external noise.

From Los Angeles Times • Sep. 19, 2023

From her front yard, Keisha Brown can see the unsightly berms of mineral wool, a byproduct of the coking process.

From Washington Post • Apr. 24, 2019

Celotex is using blast-furnace slag to make mineral wool.

From Time Magazine Archive

The easiest stuffings to procure are hay, excelsior, or paper; among others which should be covered to keep them in place are wool, mineral wool, cork, sawdust and cotton.

From The Community Cook Book by Anonymous