Natural Stone Definitions
L
Lamination
Two or more thicknesses of stone slab adhered together at an exposed edge, usually in decorative work such as countertops, creating an aesthetic effect that suggests that the stone is thicker than it actually is. Laminated edges may be dressed or profiled to a variety of shapes for additional decorative value.
Laser
An acronym for Light Amplification by Stimulated Emission of Radiation, which produces an intense narrow beam of coherent, monochromatic light. Lasers are used in the stone industry for a variety of cutting machine alignment aids, layout aids, and leveling instruments.
Lathe
Any machine that spins a block or multiple blocks of material about a horizontal axis for the purposes of creating shapes that have symmetry about the axis of rotation, such as columns, balusters, and urns.
Lead Buttons
Although not often used in modern masonry construction, these were small shims made of lead or similar malleable metal alloys used in horizontal joints to support the stones until the mortar has set.
Leathered Finish
Leathered is a special case of a brushed finish. A leathered finish is obtained by machine-brushing the stone with a range of brush coarseness. Leathered stone has a textured, pebbly surface with little pits and fissures—similar to the surface of leather. The result is a slightly undulating surface, very soft, warm, and smooth to the touch. A leathered surface has a soft patina but is not reflective. It is a slip-resistant surface, with closed pores, making it easier to maintain. Surface roughness can vary from slick (< 1/64”) to smooth (1/6 -1/16”), depending on the process.
Lewis
A lifting device consisting of multiple sections of metal forming a tapered shape which is inserted into a dovetail shaped preparation cut into the stone. Although uncommon in current industry use, lewis lifters were frequently used for hoisting quarry blocks or for heavy, cubic sections of finished stonework. Also known as “box lewis.”
Lewis Pin
A pin, usually with an eye at the upper end, used in pairs and fitted to holes drilled at opposing angles in cubic stones for hoisting purposes.
Limestone
Line (edge) Polisher
A large production machine that utilizes one or more spindles to achieve a finished edge profile on a piece of stone as it is fed through a conveying line.
Liner
An additional block or strip of stone adhered and dowelled to the back face of a stone panel for the purpose of providing a horizontal surface that can be supported by a shelf angle. The liner material may or may not be of the same stone species as the panel. Also known as “liner block” or “cleat.”
Lintel
A horizontal stone spanning over the opening of a door, window, or other opening that acts as a beam to carry the weight of the wall above it.
Lippage
The planar offset of the finished surfaces of two adjacent stone units.
Live Load
Load Cell
An electronic device (transducer) that emits an electric signal based on the force applied to the device.
Lug Sill
In stone masonry, a sill that projects into the jambs of a window or door opening (compare slip sill).
