#57 Crushed Granite is a coarse aggregate measuring mostly 1″ to 1-1/2″. The color is blue-gray, and it is a rather loose, angular landscaping stone when laid down. It provides excellent drainage around buildings or on paths and walkways, always looking clean and fresh after it rains. For purely decorative purposes, most people will prefer a rounded river stone gravel to the sharper angles of crushed granite. #57 is more often considered a utilitarian gravel for construction and roadways.
Because it drains well, this size of gravel is widely used for lining pipe trenches for irrigation, sewage or fuel lines. It is a favorite for backfilling drainage systems around buildings, and for erosion control along retaining walls. #57 stone is perfect for general purpose concrete for sidewalks and fence posts, and is the gravel size you see in bags of Ready Mix concrete at your local hardware store.
Roads & Driveways
This chunky stone is a common choice as the base layer for asphalt paving. The tar and smaller aggregates in the hot asphalt mix sink down into the spaces between these larger gravel pieces, solidifying everything into a strong, smooth and cost-efficient driving surface. On unpaved gravel roads, this size of aggregate makes an excellent top cover. It allows good drainage, stands up to heavy traffic, keeps weeds and grass down, and it looks good.
Because it does not compact well by itself, this is not a good landscaping material for steep slopes. It will readily follow gravity and rainwater down the hill. It works very well on more or less level ground around buildings, on paths and on patios if you put down a moisture-resistant layer first, such as ABC Crusher Run Gravel, erosion matting or plastic mulch.