We partner with Clayton Sand Company’s internal testing lab to verify sand gradations, allowing you to narrow down your options before paying for outsourced independent testing. The gradation index is a numerical value assigned to each mix number and determines the relative amounts of fine and coarse aggregate in the mix.

Internal testing will provide information about the sand particle size (gradation) and the uniformity coefficients (Cu). The lower the Cu and gradation index, the more uniform the particle size and the better the compaction resistance. We use several independent testing labs for verification of quality analysis or we will use the lab that you request.