Artificial ageing process, for improving appearance of concrete building blocks or paving stones, uses vibrating machine pressing tool with shaped bosses against block to cut pattern in surface

摘要

The stone or concrete block (1) may be rectangular, with a flat surface (2), and the bosses on the vibrating tool may cut an array of square and rectangular pits (5) with sloping sides (4) and flat bottoms with four, six or eight bosses. Each tool rim may have a raised rim and a flat central portion with holes set at a slightly lower level.