The Ring & Ball test is a laboratory method used to determine the softening point of bitumen, a type of petroleum-based material used in road construction and waterproofing. The test involves heating a small sample of the bitumen in a test apparatus that consists of a ring and a ball. The ring is a small metal ring with a flat base, while the ball is a small metal ball with a rounded end.

The ring and ball are placed on top of the bitumen sample, which is heated at a controlled rate. As the bitumen softens, the ball sinks into the sample and eventually falls through the ring. The temperature at which the ball falls through the ring is recorded as the softening point of the bitumen.

The Ring and Ball test is widely used in the asphalt industry to ensure the quality and consistency of bitumen used in road construction. It is also used in the research and development of new bitumen materials and in the quality control of existing bitumen products.