Via Hakai Magazine
"Sand and gravel (collectively termed aggregates) are essential for the construction industry, used mainly for building roads and producing concrete. This has led to severe shortages worldwide. According to the United Nations, global aggregate use exceeds 40 billion tonnes per year, twice the volume of sediment carried by all the world’s rivers. As more and more sand gets cemented into the built environment, beaches like Durban’s are being stripped bare by the sea."