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In the early 20th century, concrete block began to replace one of the world's oldest building materials, natural stone. Concrete block had many advantages over stone--block weighed less than stone, and were easier to set because of their uniform size and shape. Blockmaking machinery during the early 20th century was relatively sophisticated, designed to produce block by both dry and wet processes. The dry-tamp machine and the pressure machine produced block quickly with a small number of mold boxes, whereas the wet process usually involved a large number of molds and large curing areas. The lackluster appearance of common block prompted many producers to add colors or textures to their block designs. Exposed aggregates, mineral pigments and brushed textures added a pleasing appearance to this handy building material.