Natural Stone Definitions
S
Saddles
Sample
An actual piece of dimensional stone in a small size used to demonstrate the general color, markings, and finish of a given variety of stone.
Sandblasted Finish
A sandblasted finish is produced by striking the stone surface at high velocities with an abrasive material (sand) to produce a matte-textured weathered look. This machine-process generates very small craters which can highlight the color of the stone. Sandblasting creates an overall natural look. A fine particle sandblasting process produces a darker finish, whereas a coarse particle sandblasting process produces a lighter finish. Sandblasting improves slip resistance. Surface roughness can vary from slick (< 1/64”) to somewhat rough (1/16-1/4”), depending on the abrasive material used and the process.
Sandstone
Sawed Edge
A clean-cut edge generally achieved by cutting with a diamond blade.
Sawed Finish
Sawn finishes are created by using a gang saw or block cutter machine. The process creates an irregular surface with small furrows and undulations. A sawn finish makes the color of the stone appear lighter and gives the stone a matte tone. Sawn finishes can be used to create a modern look. Surface roughness can vary from slick (< 1/64”) to smooth (1/64-1/16”), depending on the process. Some fabricators will take the sawn side of the slab and apply a second finish, such a polished, honed or leathered to achieve a customized look.
Sawyer
One who operates a saw.
Scabbing
Schist
A loose term applying to foliated metamorphic (recrystallized) rock characterized by thin foliage that is composed predominantly of minerals of thin platy or prismatic habits and whose long dimensions are oriented in approximately parallel positions along the planes of foliation. Because of this foliated structure, schists split readily along these planes and so have a pronounced rock cleavage. The more common schists are composed of mica-like minerals (such as chlorite) and generally contain subordinate quartz and/or feldspar of a comparatively fine-grained texture; all gradations exist between schist and gneiss (coarsely foliated feldspathic rocks).
Scotia
A deep concave molding.
Scratched Finish
As the name implies, scratched finishes are produced by scratching the surface of the stone. This can be done by hand or by machine. They can be random or geometric. Scratching can be done before or after applying other surface finishes, which can produce a number of looks, including modern, worn, and antique. Surface roughness can vary from smooth (1/64 – 1/16”) to somewhat rough (1/16-1/4”), depending on the process.
Screed
A flat board or other straight piece used to level freshly placed concrete, mortar, or sand by sliding it over prepositioned guides that determine the height of the concrete or mortar.
Sculpture
A three-dimensional art form cut or chiseled from a monolithic block of stone.
Sealant
An elastic adhesive compound used to seal stone veneer joints while still allowing differential movement between the stone units.
Sealer
A protective coating or treatment which prevents or retards foreign liquid or matter from penetrating the stone by closing the pores on the surface.
Sealing
The process of applying a sealer.
Seam Setter
A tool designed to pull two pieces of stone together and make the surfaces flat with each other. The tools are made with suction cups and attached with a set of steel glides. The tool will allow the installer to apply adhesive, pull the stone together, shim if necessary to make flat, while the tool is holding the pieces together until the adhesive dries.
Sedimentary
Rocks formed by deposition of particles, or sediments laid down in successive strata and cemented together by another agent. The materials of which they are formed are derived from preexisting rocks or the skeletal remains of sea creatures, mainly quartz, kaolite, calcite, and dolomite
Serpentine
A common hydrous magnesium silicate rock-forming mineral, generally dark green in color with markings of white, light green, or black. Rocks composed predominantly of such minerals are correctly called “serpentinites” and are commercially sold as marble because they can be polished. The definition of serpentine is given in ASTM C119 under the marble group.
Setter
A field mechanic who specializes in the installation of dimensional stone.
Setting Space
Setting
The installation of dimensional stone units.
Shale
A fine-grained sedimentary stone formed by the compaction of clay, silt, or mud.
Shear
A force that causes, or attempts to cause, internal adjacent planes of material to slide along one another.
Shim
A piece of plastic or other non-corrosive, non-staining material used to temporarily or permanently adjust the position of a stone unit.
Shop Drawing
A detailed fabrication and installation drawing showing layout, joinery, dimensions, materials, finishes, methods of anchorage, and/or any other information pertinent to the fabrication or installation of the stone material.
Shop Ticket
A document used by a stone fabricator describing the fabrication details of an individual piece of dimensional stone, most commonly employing graphics in addition to text, and possibly including production and/or quality control monitoring. Also referred to as a “cutting” or “cut” ticket.
Shot Sawed
Description of a finish resulting from using steel shot abrasive in the gang sawing process without further embellishment. This surface will normally have random linear markings for rough surface texture.
Silica
An oxide of silicon with the chemical formula SiO2, found abundantly in nature as sand quartz, or other rock components. The dry cutting or grinding of silica will produce silica dust, which when airborne in particles of respirable size, are a well-known health hazard to those exposed to it without adequate PPE.
Siliceous
A rock bearing abundant silica.
Sill
The bottom horizontal part of a window or opening in a structure.
Siltstone
A fine-grained, non-carbonate clastic rock composed of detrital grains of quartz and silicate minerals of silt size. Siltstones are rarely marketed as such but commonly are considered as fine-grained, quartz-based stones (sandstones). Siltstone is texturally transitional between quartz-based stones and shales (mudstones). Many bluestones and siliceous flagstones fall within this category. The term is included in these definitions chiefly to explain the relationship of some siliceous flagstones to the quartz-based stone category.
Simulated Stone
An artificial man-made product that attempts to resemble natural stone.
Slab
A flat sheet-like section of natural stone sawn to a prescribed thickness, with length and width determined by the size of the quarry block from which it was sawed. Slabs will generally receive a face finish and further fabrication processes to become usable dimensional stone products.
Slate
Sling
A type of strap, typically in the form of a loop, made of high-density cloth and rated for the intended load, which is wrapped around an object that is being lifted.
Slip Joint
A connection that permits vertical or horizontal movement of a stone unit relative to the adjacent unit.
Slip Sill
A stone sill set between jambs. (compare lug sill).
Slurry
A suspension of insoluble particles in a liquid.
Smooth Finish
A finish of minimum textural quality, presenting the least interruption of surface. Smooth finish may be applied to any surface, flat or molded. It is produced by a variety of machines.
Snapped Edge
Soapstone
A talc-rich stone with a soapy feel, used for hearths, tabletops, chemical-resistant laboratory tops, stove facings, and cladding; known for its heat, chemical, and stain-resistant properties.
Soffit
The underside of any architectural element, such as an arch, beam, lintel, or balcony.
Soundness
A property of stone used to describe relative freedom from cracks, faults, voids, and similar imperfections found in the untreated stone. One of the characteristics encountered in fabrication.
Spall
A chip or splinter separated from the main mass of a stone. Also known as “sprawl.”
Spandrel
- The often-decorated triangular area between an arch and a wall, or between two arches.
- In modern high-rise construction, the panel area between the head of one window and the sill of the one above it. Can be clad in stone, metal, or glass.
Splay
A surface that makes an oblique angle with another surface, such as the non-vertical riser face frequently seen on steps.
Split
Division of a rock by cleavage.
Split-face Stone
Stone on which the face has been broken to an approximate plane.
- Split-face Natural Bed: Stone that’s sawn against the grain so it shows the natural bed grain of the stone, just as it was formed.
- Split-face Sawed Bed: Most often sawn on the beds and is split either with a machine or by hand, so the surface face of the stone shows the natural quarry texture.
Split-face Finish
Split-face stone has been broken by a hydraulic splitter to a specific size, producing a natural look. This finish is mostly used for veneer. It exhibits a natural, quarry texture with untrimmed edges. Split-face stone generally has a flat back and uneven front surface. The surface evenness varies with the stone type. Faces can be convex, concave or flat. Split-face finishes come in a number of variations including flat-plane and rough-plane. Flat-plane surface roughness can vary from somewhat rough (1/16-1/4”) to rough (1/4-2″). Rough-plane surface roughness can vary from rough to very rough (>2”). While fabrication can be machine-made, hand-made versions are generally considered more attractive. Rockfaced finishes can look similar to split-face.
Spot or Spotting
The mortar applied to the back of dimensional stone veneer to bridge the space between a stone panel and the backup wall. Often used to describe the plaster or mortar spot used with wire tie anchorage.
Spreader Bar
A beam with two lifting slings or cables, one on each end, intended to spread the lifting points while the bar is hoisted from its center.
Stacked Bond
Stone that is cut to one dimension and installed with unbroken vertical and horizontal joints running the entire length and height of the veneered area.
Statuary
A stone sculpture of an animal or human figure.
Sticking
The butt edge repair of a broken piece of stone, now generally done with dowels, cement, or epoxies. The pieces are stuck together; thus “sticking.”
Stone
Sometimes synonymous with rock, but more properly applied to individual blocks, masses or fragments taken from their original formation or considered for commercial use. In commercial use, the term stone is more frequently used, while scientifically, geologists and petrographers more frequently use the term rock.
Stool
The interior sill of a window.
Stratification
The layered structure in sedimentary stone deposits as a result of the deposition of sediments in beds or layers (also “strata” or “lamina”).
String Course
A horizontal band of masonry, generally narrower than other courses, extending across the façade of a structure and in some structures encircling such decorative features as pillars or engaged columns. May be flush or projected, and flat-surfaced or decorated. Also called “belt course” or “band course.”
Stripping
To remove coatings that block a stone’s ability to breathe which may cause spalling (when the stones crack, pop, or shale). Some examples of common coatings are topical acrylic sealers, janitorial waxes, and polyurethanes.
Stylolite
Stylolites or styolite (Greek: stylos, pillar; lithos, stone) are serrated surfaces within a rock mass at which mineral material has been removed by pressure dissolution, in a process that decreases the total volume of rock. Also known as “crowfoot.”
Support
An angle, plate or other stones that carry a gravity load.
