Rockwool International A/S

Rockwool International A/S, also known as the ROCKWOOL Group, is a Danish multinational manufacturer of mineral wool products headquartered in Hedehusene in greater Copenhagen. Production of mineral, or stone, wool began at the site in 1937 under an American license, and by 1939 the company had turned fully to making insulation; it began trading as Rockwool International A/S on the Copenhagen Stock Exchange in 1995. The company was the world's largest maker of insulation materials in 2009, fell to second largest by 2016, and today describes itself as the world's leading manufacturer of stone wool insulation, made by heating minerals to their melting point and spinning them into fine threads used to insulate buildings. This description is adapted from Wikipedia contributors under CC BY-SA 4.0; changes were made. https://creativecommons.org/licenses/by-sa/4.0/