Mortar joint

In masonry, mortar joints are the spaces between bricks, concrete blocks, or glass blocks, that are filled with mortar or grout. If the surface of the masonry remains unplastered, the joints contribute significantly to the appearance of the masonry. Mortar joints can be made in a series of different fashions, but the most common ones are raked, grapevine, extruded, concave, V, struck, flush, weathered and beaded.