Blue metal dust is a byproduct of crushing blue metal (basalt rock), and it consists of fine particles that are highly compactable. It’s primarily used as a base material for driveways, paths, and under concrete slabs. When compacted, blue metal dust forms a strong, solid surface that offers excellent load-bearing properties, which makes it ideal for areas with heavy traffic. It also works well as a filler material for landscaping, helping to level surfaces before other materials are laid on top. Its distinctive blue-grey color is a feature of basalt, and it binds tightly when wet, offering additional strength.