Washed rock has a smooth, rounded appearance and is useful for several different applications, depending on the size.
- Pea gravel is the smallest type of washed gravel, about 3/8-inch in size. It contains a spectrum of colors and as a result, is often used in above ground applications when visual appearance is important.
- Drainage gravel is larger – about 1 ½-inches in size and as the name implies, is useful for septic systems, French drains, and drainage systems.
- Smaller drainage gravel ranges between ¾-inch to 7/8-inches in size and is useful for landscaping and gardening projects requiring more substantial rock than pea gravel.
- Cobbles, are rounded washed rock pieces, range in size from 1-inch (about marble-sized) up to 8-inch (a small basketball). These washed rocks can be used in loose form in landscaped areas for decorative ground cover, in waterway beds or in flower beds. When incorporated with cement mortar, cobbles form unique pathways or drives.