what is the preferred mositure content in aggregates for use

what is the preferred mositure content in aggregates for use in concrete? If this moisture content cannot be achieved, is it better for the aggregate to be wetter or drier? Why?

Solution

it is preferred to be to be Saturated Surface Dry (SSD), meaning all the void spaces are filled but there is no excess moisture on the surface. Wetter aggregate is better because it is easy to calculate how much excess water mass is on the surface of the aggregate beyond SSD condition. The excess water on the aggregate will make up a portion of the water in W/C ratio