Uh, for concrete the granularity and composition is VERY important. In fact it's one of the most important parameters you can tweak in a concrete mix. To the p

Uh, for concrete the granularity and composition is VERY important. In fact it's one of the most important parameters you can tweak in a concrete mix. To the point that weird stuff like this happens quite frequently: https://www.quora.com/Is-it-true-that-Saudi-Arabia-imports-sands-from-Australia-If-so-why https://www.quora.com/Is-it-true-that-Saudi-Arabia-imports-s... My local DIY store here in the UK carries some 8 different types of sand, all for different purposes.