Minimum index density, minimum unit weight
The minimum index density/unit weight represents the loosest condition of a cohesionless, free-draining soil that can be attained by a standard laboratory procedure, which prevents bulking and minimizes particle segregation. Any particular procedure selected will consist of determining the density/unit weight of oven-dried soil placed into a container of known volume in such a manner that prevents bulking and particle segregation, and minimizes compaction of the soil.
0.1 ft³ to 0.5 ft³, depending on maximum particle size
Minimum index density, minimum index unit weight, relative density