Pottery Barn's Found Vintage Grain Sack Pillow Covers sell for $89 to $99. Ranging in age from 50 to 80 years old, these beautifully handwoven vintage muslin sacks were once used by farmers in Eastern Europe for transporting grains to the mill. Monogrammed pieces have cross-stitched initials that were once used by farmers to identify them after milling. Slight marks and variations distinguish these grain sacks as authentic vintage pieces.