The facade bricks (non-perforated) have five sand covered sides and one side with possible oblong groove. The structure looks rugged with fine and irregular grooves in the sandy surface. The baking process takes place in a gas-heated tunnel oven under slightly reduced atmosphere.
The baking process is done in a gas-fired tunnel kiln under a slightly reducing atmosphere. The colour of the Roca is silver grey interspersed with dark colour deposits.
The colours shown are a near reflection of reality.