The Domtar Mine, formed from the consolidation of Grand Rapids Gypsum Company mines 1 & 2, is an inactive underground gypsum mine in Walker, a suburb of Grand Rapids, Michigan.

Butterworth, who opened the first gypsum mines north of the Grand River in this area.

[1] A small gypsum solutional cave, known as the Pellerito Cave (named after its founder, Russell Pellerito) was discovered during the mining operations.

[3] Domtar sold their gypsum operations to Georgia-Pacific, who closed the mine in 1999.

It was the last operating underground gypsum mine in Michigan.