Natural, artificial and machined stones; marble, cement mixes, concrete, non-agricultural lime for use in construction, mortar, sandstone, plaster and gravel; earth for bricks; refractory materials, refractory compositions and materials for industrial use, namely refractory cement mixes, refractory concrete, refractory mortar, firestone and refractory brick; refractory clay for furnaces and furnace coverings in the form of unprocessed or partly shaped mineral material; refractory materials fo...