Manufactured sand usage is increasing in concrete as re- sources of natural, fine aggregate become scarcer. Modern processing of these manufactured sands has the potential to reduce the need for blending with natural sands that are often extracted from sensitive environments. Typically, older technology use impact crushers that produce poorly shaped particles and washing is done to remove excess fines. Modern processing using vertical shaft impact (VSI) crushers and air screening can produce better quality man- ufactured sand, sometimes referred to as engineered or modern processed sand. These materials consistently have better grading and particle shape and less problematic ul- tra-fine particles.