Gravel is sized to model gravel roads more realistically. Use Accent for shoulders and to model bare spots on roads.

Gravel- 10.8 in3 (176 cm3)
Accent Powder- 1.8 in3 (29.4 cm3)
Coverage: Models a gravel road 14' x 2" (4.26 m x 5.08 cm)

Actual coverage depends on usage.