Basalt
| Countertop
| Density
| Dolomite
| Granite
| Graphic Texture
| Igneous Rock
| Kinds of marble
| Limestone
Marble
| Metamorphic Rock
| Quarry
| Quartz
| Sandstone
| Soapstone
| Slate
| Travertine .......
Glossary
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Basalt is a common extrusive volcanic rock. It is usually grey to black and fine-grained due to rapid cooling of lava at the surface of a planet.
It may be porphyritic containing larger crystals in a fine matrix, or vesicular, or frothy scoria. Unweathered basalt is black or grey.
On Earth, most basalt magmas have formed by decompression melting of the mantle. Basalt has also formed on Earth's Moon, Mars, Venus, and even on the asteroid Vesta. Source rocks for the partial melts probably include both peridotite and pyroxenite . The crustal portions of oceanic tectonic plates are composed predominantly of basalt, produced from upwelling mantle below ocean ridges.
The term basalt is at times applied to shallow intrusive rocks with a composition typical of basalt, but rocks of this composition with a phaneritic (coarse) groundmass are generally referred to as diabase (also called dolerite) or gabbro.
Morphology and textures
The shape, structure and texture of a basalt is diagnostic of the way it erupted and where it erupted - whether into the sea, in an explosive cinder eruption or as creeping pahoehoe lava flows, the classical image of Hawaiian basalt eruptions.
Subaerial eruptions
Basalt which erupts under open air (that is, subaerially) forms three distinct types of lava or volcanic deposits: scoria, ash or cinder; breccia and lava flows.
Basalt in the tops of subaerial lava flows and cinder cones will often be highly vesiculated, imparting a lightweight "frothy" texture to the rock. Basaltic cinders are often red, coloured by oxidised iron from weathered iron-rich minerals such as pyroxene.
'A'a types of blocky, cinder and breccia flows of thick, viscous basaltic magma are common in Hawaii and other basalts which erupt slightly cooler. Pahoehoe is a highly fluid, hot form of basalt which tends to form thin aprons of molten lava which fill up hollows and form lava lakes. Lava tubes are common features of pahoehoe eruptions.
Basaltic tuff or pyroclastic rocks are rare but not unknown. Usually basalt is too hot and fluid to build up sufficient pressure to form explosive lava eruptions but occasionally this will happen by trapping of the lava within the volcanic throat and build up of volcanic gases. Hawaii's Mauna Loa erupted in this way in the 19th century. Another example is the 0.2Ma Diamond Head Tuff, Hawaii.
Maar volcanoes are typical of small basalt tuffs, formed by explosive eruption of basalt through the crust, forming an apron of mixed basalt and wall rock breccia and a fan of basalt tuff further out from the volcano.
Amygdaloidal structure is common in relic vesicles and beautifully crystallized species of zeolites, quartz or calcite are frequently found.
Columnar basalt is formed by cooling of a thick lava flow, which forms contractional joints or fractures. If a flow cools relatively rapidly, significant contraction forces build up. While a flow can accommodate shrinking in the vertical direction (the flow becomes less thick), it cannot easily accommodate shrinking in the horizontal direction unless cracks form. The extensive fracture network that develops results in the formation of columns. Because hexagons fit together efficiently with no vacant space (a tessellation), this is the most common pattern that develops. Pentagonal, heptagonal or octagonal joint patterns are also known, but are less common. Note that the size of the columns depends loosely on the rate of cooling; very rapid cooling may result in very small (<1 cm diameter) columns, and vice versa.
Submarine eruptions
Pillow Basalts When basalt erupts underwater or flows into the sea, the cold water quenches the surface and the lava forms a distinctive pillow shape, through which the hot lava breaks to form another pillow. This pillow texture is very common in underwater basaltic flows and is diagnostic of an underwater eruption environment when found in ancient rocks. Pillows typically consist of a fine-grained core with a glassy crust and have radial jointing. Size of individual pillows vary from 10 cm up to several metres.
When pahoehoe lava enters the sea it usually forms pillow basalts. However when a'a enters the ocean it forms a littoral cone, a small cone-shaped accumulation of tuffaceous debris formed when the blocky a'a lava enters the water and explodes from built-up steam.
The island of Surtsey in the Atlantic is a basalt volcano which breached the ocean surface in 1963. The initial phase of Surtsey's eruption was highly explosive, as the magma was quite wet, causing the rock to be blown apart by the boiling steam to form a tuff and cinder cone. This has subsequently moved to a typical pahoehoe type behaviour.
Glass or obsidian may be present, particularly as rinds on rapidly chilled surfaces of lava flows, and is commonly (but not exclusively) associated with underwater eruptions. Distribution
The lava flows of the Deccan Traps in India, the Siberian Traps in Russia, the Columbia River Plateau of Washington and Oregon states in the United States, as well as the Triassic lavas of eastern North America are basalts. Other famous accumulations of basalts include Iceland and the islands of the Hawaii volcanic chain, forming above a mantle plume.
Perhaps the most famous basalt flow in the world is the Giant's Causeway on the northern coast of Ireland, in which the vertical joints form hexagonal columns and give the impression of having been artificially constructed.
Ancient precambrian basalts are usually only found in fold and thrust belts, and are often heavily metamorphosed. These are known as greenstone belts. Jade or nephrite is a gem mineral found in metamorphosed basalts.
Pliny used the word basalt and it is said to have had an Ethiopian origin, meaning a black stone.
Lunar basalt
The dark areas visible on Earth's moon, the lunar maria, are plains of basalt and gabbro, and basalt Moon samples were brought to Earth by the astronauts of the Apollo program.
Lunar basalts show exotic textures and mineralogy, particularly shock metamorphism, lack of the oxidation typical of terrestrial basalts, lack of hydration and peculiar geochemistry. Their short period of eruption is considered to be related to the swift cooling of the Moon's magma ocean after the satellite formed from a theorised impact with a Mars-sized body.
Types of basalt
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Countertop (also counter top, countertopping, benchtop, or (British English) worktop) usually refers to a horizontal worksurface in kitchens, other food preparation areas, and workrooms in general. It is frequently installed above and supported by cabinets.
Kitchen countertops
When installed in a kitchen, countertops are usually about 25 1/2 inches (650 mm) from front to back and are designed to slightly-overhang standard kitchen base cabinets. This allows a convenient reach to objects at the back of the countertop. They often contain some sort of integrated backsplash to prevent spilled liquids from falling behind the cabinets and the face of the countertop may be decorated in ways ranging from plain to very elaborate. They may be cut away to accommodate the installation of sinks, stoves (cookers), ranges, and cooktops, or other accessories such as integrated drain boards and cutting boards.
Materials
Countertops can be made from a very wide range of materials and the cost of the completed countertop can vary very widely depending on the material chosen. The durability and ease of use of the material often rises with the increasing cost of the material but this is not necessarily so; some very expensive materials are neither particularly durable nor easy to use, just stylish. Some common materials are as follows:
Stainless steel
Crafted glass
Natural stones:
Natural stone
The natural stone or dimension stone slab (e.g. granite) is shaped using cutting and finishing equipment in the shop of the fabricator. The edges are commonly put on by hand-held routers, grinders, or CNC equipment. If the stone has a highly varigated pattern, the stone is laid out in final position in the shop for the customer's inspection. Then the countertop assembly is installed on the job site by professionals.
Crafted glass
Custom architectural crafted glass, tempered glass, textured glass pieces, and the ancient art of reverse gilded glass, are applied to contemporary uses including countertops, backsplashes, and tabletops. Glass work may be customized to suit by craftsmen in the studio, then installed on site either in small components or as immense, single units (for example, a glass countertop and sink basin formed of one continuous piece of textured glass). The glass is non-porous, relatively stain-proof, extremely hygienic, and "extremely heat resistant (up to 700 degrees)." Much work is being done to "recycle" glass using sources such as post consumer glass or post industrial float glass. The material can be crushed or cut into strips that is heated until the softening point of glass, binding the loose material back into a solid form.
Tile
Tile, including ceramic tile and stone tile, is installed in much the same way as flat lay laminate except that the gaps between the tiles are grouted after the tile has been glued down.
Engineered quartz surfacing
Engineered quartz surfacing is made from approximately 95% natural quartz and 5% polymer resins. Testing has shown that they retain much of the toughness of quartz but display increased ductility due to the resin, improving impact resistance. Countertops are custom made and are more scratch resistant as well as less porous than natural quartz surfaces. Thicknesses may be 6mm, 1.2 cm (1/2 inch), 2 cm (3/4 inch), 3 cm (1 1/4 inch) or 4 cm (1 1/2 inch). Brands include Hanstone,NaturaStone, Silestone, Q, Caesarstone,Technistone, Cambria, and Zodiaq.
Other materials
Stainless steel, stone, concrete, terrazzo, and other materials are usually prefabricated and assembled on site as well. The difficulty of prefabrication rises with the more exotic materials. As with solid-surface plastic materials, the edge treatments can vary widely, but the material is usually thicker than with plastic so there is often no need to build up the edge with multiple layers of the material.
Many predesigned, prefabricated units (including sinks, drainboards, and other accessories) are available in stainless steel. These may be used "stand-alone" or integrated into larger custom assemblies. Some stainless steel systems stand on their own legs and do not require the support of cabinetry.
Sink installation
In any of these styles, "self-rimming" sinks can be used. These sit in appropriately-shaped holes cut in the countertop (or substrate material) using a jigsaw or other cutter appropriate to the material at hand and are suspended by their rim. The rim then inherently forms a fairly close seal with the top surface of the countertop, especially when the sink is clamped into the hole from below.
The materials also allow the installation of a "bottom-mount" or "under-mount" sink. With these, the edge of the countertop material is exposed at the hole
created for the sink (and so must be a carefully finished edge rather than a rough cut; this cut is generally done at the fabricator's workshop). The sink is
then mounted to the bottom of the material from below. Especially for under-mount sinks, silicone-based sealants are usually used to assure a waterproof joint
between the sink and the countertop material. The advantage of an "under-mount" sink is that it gives a contemporary look to the kitchen but the disadvantages
are extra cost in both the sink and the counter top.
Solid-surface plastic materials allow a third option: sinks made of the same plastic material as the countertop can easily be glued to the underside of the countertop material and the joint sanded flat, creating the usual invisible joint and completely eliminating any dirt-catching seam between the sink and the countertop. The disadvantage is that the sinks do not have the same impact resistance of stainless or cast iron and may differentially expand and contract with extreme temperature change (as might be caused by a pot of hot water dumped into the sink). In a similar fashion, with stainless steel, a sink may be welded into the countertop; the joint is then ground to create a finished, concealed appearance.
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Density (Greek: rho) is a measure of mass per unit of volume. The higher an object's density, the higher its mass per volume. The average density of an object equals its total mass divided by its total volume. A denser object (such as iron) will have less volume than an equal mass of some less dense substance (such as water). The SI unit of density is the kilogram per cubic metre (kg/m3)
Under specified conditions of temperature and pressure, the density of a fluid is defined as described above. However, the density of a solid material can be different, depending on exactly how it is defined. Take sand for example. If you gently fill a container with sand, and divide the mass of sand by the container volume you get a value termed loose bulk density. If you took this same container and tapped on it repeatedly, allowing the sand to settle and pack together, and then calculate the results, you get a value termed tapped or packed bulk density. Tapped bulk density is always greater than or equal to loose bulk density. In both types of bulk density, some of the volume is taken up by the spaces between the grains of sand.
Also, in terms of candy making, density is affected by the melting and cooling processes. Loose granular sugar, like sand, contains a lot of air and is not tightly packed, but when it has melted and starts to boil, the sugar loses its granularity and entrained air and becomes a fluid. When you mold it to make a smaller, compacted shape, the syrup tightens up and loses more air. As it cools, it contracts and gains moisture, making the already heavy candy even more dense.
Other units
Density in terms of the SI base units is expressed in kilograms per cubic meter (kg/m3). Other units fully within the SI include grams per cubic centimetre (g/cm3) and megagrams per cubic metre (Mg/m3). Since both the litre and the tonne or metric ton are also acceptable for use with the SI, a wide variety of units such as kilograms per litre (kg/L) are also used. Imperial units or U.S. customary units, the units of density include pounds per cubic foot (lb/ft3), pounds per cubic yard (lb/yd3), pounds per cubic inch (lb/in3), ounces per cubic inch (oz/in3), pounds per gallon (for U.S. or imperial gallons) (lb/gal), pounds per U.S. bushel (lb/bu), in some engineering calculations slugs per cubic foot, and other less common units.
The maximum density of pure water at a pressure of one standard atmosphere is 999.861kg/m3; this occurs at a temperature of about 3.98 C (277.13 K).
From 1901 to 1964, a litre was defined as exactly the volume of 1 kg of water at maximum density, and the maximum density of pure water was 1.000 000 kg/L (now 0.999 972 kg/L). However, while that definition of the litre was in effect, just as it is now, the maximum density of pure water was 0.999 972 kg/dm3. During that period students had to learn the esoteric fact that a cubic centimetre and a millilitre were slightly different volumes, with 1 mL = 1.000 028 cm3. (often stated as 1.000 027 cm3 in earlier literature).
Measurement of density
A common device for measuring fluid density is a pycnometer. A device for measuring absolute density of a solid is a gas pycnometer. Density of substances
Perhaps the highest density known is reached in neutron star matter (see neutronium). The singularity at the centre of a black hole, according to general relativity, does not have any volume, so its density is undefined.
The most dense naturally occurring substance on Earth is iridium, at about 22650 kg/m3. A table of densities of various substances:
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Note the low density of aluminium compared to most other metals. For this reason, aircraft are made of aluminium. Also note that air has a nonzero, albeit small, density. Aerogel is the world's lightest solid.
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Dolomite is the name of both a carbonate rock and a mineral consisting of calcium magnesium carbonate (formula: CaMg(CO3)2) found in crystals.
Dolomite rock (also dolostone) is composed predominantly of the mineral dolomite. Limestone which is partially replaced by dolomite is referred
to as dolomitic limestone, or in old U.S. geologic literature as magnesian limestone.
Dolomite mineral crystallizes in the trigonal - rhombohedral system. It forms white, gray to pink, commonly curved crystals, although it is usually massive. It has physical properties similar to those of the mineral calcite, but does not rapidly dissolve or effervesce (fizz) in dilute hydrochloric acid. The Mohs hardness is 3.5 to 4 and the specific gravity is 2.85.
Dolomite was first described in 1791 as the rock by the French naturalist and geologist, Deodat Guy Tancrede de Gratet de Dolomieu (1750-1801) for exposures in the Dolomite Alps of northern Italy.
Formation
There is significant uncertainty regarding the cause of dolomite formation. Vast deposits are present in the geological record, but the mineral is relatively rare in modern environments. This is referred to as the "Dolomite Problem". Dolomite accounts for about 10% of all sedimentary rock, i ncluding much that would have been produced near the surface of the Earth. However, laboratory synthesis of undisputed dolomite has been carried out only at temperatures of greater than 100 degrees Celsius, conditions typical of burial in sedimentary basins - even though much dolomite in the rock record appears to have formed in low-temperature conditions. The high temperature is likely to speed up the movement of calcium and magnesium ions so that they can find their places in the ordered structure within a reasonable amount of time. This suggests that the lack of dolomite that is being formed today is likely due to kinematic factors.
Modern dolomite does occur as a precipitating mineral in specialized environments on the surface of the earth today. In the 1950's and 60's, dolomite was found to be forming in highly saline lakes in the Coorong region of South Australia. Dolomite crystals also occur in deep-sea sediments, where organic matter content is high. This dolomite is termed "organogenic" dolomite.
Recent research has found modern dolomite formation under anaerobic conditions in supersaturated saline lagoons along the Rio de Janeiro coast of Brazil, namely, Lagoa Vermelha and Brejo do Espinho. One interesting reported case was the formation of dolomite in the kidneys of a dalmatian dog. This was believed to be due to chemical processes triggered by bacteria. Dolomite has been speculated to develop under these conditions with the help of sulfate-reducing bacteria. This joins other research in pointing out many new interesting links between large-scale geology and small-scale microbiology (see geomicrobiology).
The actual role of bacteria in the low-temperature formation of dolomite remains to be demonstrated. The specific mechanism of dolomitization, involving
sulfate-reducing bacteria, has not yet been demonstrated.
Dolomite appears to form in many different types of environment and can have varying structural, textural and chemical characteristics. Some researchers have stated "there are dolomites and dolomites," meaning that there may not be one single mechanism by which dolomite can form. Much modern dolomite differs significantly from the bulk of the dolomite found in the rock record, leading researchers to speculate that environments where dolomite formed in the geologic past differ significantly from those where it forms today.
Reproducible laboratory syntheses of dolomite (and magnesite) leads first to the initial precipitation of a metastable "precursor" (such as magnesium calcite), to be changed gradually into more and more of the stable phase (such as dolomite or magnesite) during periodical intervals of dissolution and reprecipitation. The general principle governing the course of this irreversible geochemical reaction has been coined "Ostwald's Step Rule".
Uses
Dolomite is used as an ornamental stone, as a raw material for the manufacture of cement, and as a source of magnesium oxide. It is an important petroleum reservoir rock, and serves as the host rock for large strata-bound Mississippi Valley-Type (MVT) ore deposits of base metals (that is, readily oxidized metals) such as lead, zinc, and copper. Where calcite limestone is uncommon or too costly, dolomite is sometime used in its place as a flux (impurity remover) for the smelting of iron and steel.
In horticulture, dolomite and dolomitic limestone are added to soils and soilless potting mixes to lower their acidity ("sweeten" them). Home and container gardening are common examples of this use. In nutrition, dolomite is sold sometimes as a dietary supplement on the assumption that it should make a good simultaneous source of the two important elemental nutrients calcium and magnesium. However, since dolomites from Mississippi Valley-Type ore regions such as the Old Lead Belt and New Lead Belt in southeastern Missouri often include significant levels of lead and other toxic elements, users should always verify that such dolomite supplements are from non-ore regions of the world before ingesting them. A far safer strategy is to avoid using dolomite as a supplement altogether, and instead taking equivalent amounts of milk of magnesia and calcium supplements. The chemical processes used to create such individual supplements effectively eliminate the risk of ingesting the toxic metals often associated with raw dolomite.
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Granite is a common and widely occurring type of intrusive, felsic, igneous rock. Granites usually have a medium to coarse grained texture. Occasionally
some individual crystals (phenocrysts) are larger than the groundmass in which case the texture is known as porphyritic. A granitic rock with a porphyritic
texture is sometimes known as a porphyry. Granites can be pink to dark gray or even black, depending on their chemistry and mineralogy. Outcrops of granite
tend to form tors, and rounded massifs. Granites sometimes occur in circular depressions surrounded by a range of hills, formed by the metamorphic aureole or
hornfels.
Granite is nearly always massive (lacking internal structures), hard and tough, and therefore it has gained widespread use as a construction stone. The average density of granite is 2.75 g/cm3.
The word granite comes from the Latin granum, a grain, in reference to the coarse-grained structure of such a crystalline rock.
Mineralogy
Granite is classified according to the QAPF diagram (a QAPF diagram is a double triangle diagram which is used to classify igneous rocks based on mineralogic composition. The acronym, QAPF, stands for "Quartz, Alkali feldspar, Plagioclase, Feldspathoid (Foid)".) for coarse grained plutonic rocks (granitoids) and is named according to the percentage of quartz, alkali feldspar (orthoclase, sanidine, or microcline) and plagioclase feldspar on the A-Q-P half of the diagram. True granite according to modern petrologic convention contains both plagioclase and alkali feldspars. When a granitoid is devoid or nearly devoid of plagioclase the rock is referred to as alkali granite. When a granitoid contains less than 10% orthoclase it is called tonalite; pyroxene and amphibole are common in tonalite. A granite containing both muscovite and biotite micas is called a binary or two-mica granite. Two-mica granites are typically high in potassium and low in plagioclase, and are usually S-type granites or A-type granites. The volcanic equivalent of plutonic granite is rhyolite. Granite has poor primary permeability but strong secondary permeability.
Chemical composition A worldwide average of the average proportion of the different chemical components in granites, in descending order by weight percent, is:
Based on 2485 analyses
Occurrence
Granite is currently known only on Earth where it forms a major part of continental crust. Granite often occurs as relatively small, less than 100 km2 stock masses (stocks) and in batholiths that are often associated with orogenic mountain ranges. Small dikes of granitic composition called aplites are often associated with the margins of granitic intrusions. In some locations very coarse-grained pegmatite masses occur with granite.
Granite has been intruded into the crust of the Earth during all geologic periods, although much of it is of Precambrian age. Granitic rock is widely distributed throughout the continental crust of the Earth and is the most abundant basement rock that underlies the relatively thin sedimentary veneer of the continents.
Origin
Granite is an igneous rock and is formed from magma. Granitic magma has many potential origins but it must intrude other rocks. Most granite intrusions are emplaced at depth within the crust, usually greater than 1.5 kilometres and up to 50 km depth within thick continental crust. The origin of granite is contentious and has led to varied schemes of classification. Classification schemes are regional and include French, British, and American systems.
Geochemical origins
Granitoids are a ubiquitous component of the crust. They have crystallized from magmas that have compositions at or near a eutectic point (or a temperature minimum on a cotectic curve). Magmas will evolve to the eutectic because of igneous differentiation, or because they represent low degrees of partial melting. Fractional crystallisation serves to reduce a melt in iron, magnesium, titanium, calcium and sodium, and enrich the melt in potassium and silicon - alkali feldspar (rich in potassium) and quartz (SiO2), are two of the defining constituents of granite.
This process operates regardless of the origin of the parental magma to the granite, and regardless of its chemistry. However, the composition and origin of the magma which differentiates into granite, leaves certain geochemical and mineral evidence as to what the granite's parental rock was. The final mineralogy, texture and chemical composition of a granite is often distinctive as to its origin. For instance, a granite which is formed from melted sediments may have more alkali feldspar, whereas a granite derived from melted basalt may be richer in plagioclase feldspar. It is on this basis that the modern "alphabet" classification schemes are based.
Granitization
An old, and largely discounted theory, granitization states that granite is formed in place by extreme metasomatism by fluids bringing in elements e.g. potassium and removing others e.g. calcium to transform the metamorphic rock into a granite. This was supposed to occur across a migrating front. The production of granite by metamorphic heat is difficult, but is observed to occur in certain amphibolite and granulite terrains. In-situ granitisation or melting by metamorphism is difficult to recognise except where leucosome and melanosome textures are present in gneisses. Once a metamorphic rock is melted it is no longer a metamorphic rock and is a magma, so these rocks are seen as a transitional between the two, but are not technically granite as they do not actually intrude into other rocks. In all cases, melting of solid rock requires high temperature, and also water or other volatiles which act as a catalyst by lowering the solidus temperature of the rock.
Uses
Antiquity
The Red Pyramid of Egypt (c.26th century BC), named for the light crimson hue of its exposed granite surfaces, is the third largest of Egyptian pyramids. Menkaure's Pyramid, likely dating to the same era, was constructed of limestone and granite blocks. The Great Pyramid of Giza (c.2580 BC) contains a huge granite sarcophagus fashioned of "Red Aswan Granite." The mostly ruined Black Pyramid dating from the reign of Amenemhat III once had a polished granite pyramidion or capstone, now on display in the main hall of the Egyptian Museum in Cairo (see Dahshur). Other uses in Ancient Egypt include columns, door lintels, sills, jambs, and wall and floor veneer. How the Egyptians worked the solid granite is still a matter of debate. Dr. Patrick Hunt has postulated that the Egyptians used emery shown to have higher hardness on the Mohs scale.
Many large Hindu temples in southern India, particularly those built by the 11th century king Rajaraja Chola I, were made of granite. There is a large amount of granite in these structures. They are comparable to the Great Pyramid of Giza.
Modern
Building
Granite has been extensively used as a dimension stone and as flooring tiles in public and commercial buildings and monuments. Because of its abundance,
granite was commonly used to build foundations for homes in New England. The Granite Railway, America's first railroad, was built to haul granite from the
quarries in Quincy, Massachusetts, to the Neponset River in the 1820s. With increasing amounts of acid rain in parts of the world, granite has begun to
supplant marble as a monument material, since it is much more durable. Polished granite is also a popular choice for kitchen countertops due to its high
durability and aesthetic qualities. In building and for countertops, the term "granite" is often applied to all igneous rocks with large crystals, and not
specifically to those with a granitic composition.
Other uses
Curling stones are traditionally fashioned of Ailsa Craig granite. The first stones were made in the 1750s, the original source being Ailsa Craig in Scotland. Because of the particular rarity of the granite, the best stones can cost as much as US$1,500. Between 60-70 percent of the stones used today are made from Ailsa Craig granite, although the island is now a wildlife reserve and is no longer used for quarrying.
In some areas granite is used for gravestones and memorials. Granite is a hard stone and requires skill to carve by hand. Modern methods of carving include using computer-controlled rotary bits and sandblasting over a rubber stencil. Leaving the letters, numbers and emblems exposed on the stone, the blaster can create virtually any kind of artwork or epitaph. Granite gravestone in Hingham, Massachusetts
Engineering
Engineers have traditionally used polished granite surfaces to establish a plane of reference, since they are relatively impervious and inflexible. Sandblasted concrete with a heavy aggregate content has an appearance similar to rough granite, and is often used as a substitute when use of real granite is impractical. A most unusual use of granite was in the construction of the rails for the Haytor Granite Tramway, Devon, England, in 1820.
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Acid-Washed Finish
An acid-washed finish is shiny with small etching marks (pits in the surface). This finish shows fewer scratches and is much more rustic
in appearance than a honed finish. Most stones can be acid-washed but the most common are marble and limestone. Acid washing is also a
way to soften the shine on granite.Brushed Finish
Brushed features a worn-down look achieved by brushing the surface of the stone, simulating natural wear over time.Bull Nose Edge
One of two types of edges for natural stone floor tile. A polished bull nose edge has a rounded or curved appearance.Calibrated
During this stage, the stone slab's surface is worked down to a relatively uniform thickness across the length of the material.CBU
Wood subfloors usually require a CBU or cement backer unit for support and a moisture barrier.Ditra
An underlayment that provides a solid foundation for the tile, while still allowing for slight movement of the substrate without damage.
Plus, in the event that water penetrates the grout, in a bathroom for example, it provides a protective waterproof barrier.Fabricator
At the fabricator's facility the natural stone slabs are customized for specific installations.Flamed Finish
A flamed finish is achieved by heating the surface of the stone to extreme temperatures, followed by rapid cooling.
The surface of the stone pops and chips leaving a rough, unrefined texture. This process is usually done with granite. Flamed granite
has a highly textured surface, making it ideal for areas where slip resistance might be a concern, like shower areas.Granite
An igneous stone that is extremely hard, dense and resistant to scratches and acid etching. It is an ideal stone for use in flooring
and in food preparation areas. Hundreds of varieties of granite exist.Honed Finish
A honed surface provides a flat, matte or satin finish creating a more informal and softer look. This finish is created by stopping
short of the last stage of polishing. A honed finish shows fewer scratches, and requires very little maintenance.Igneous Rock
Formed when molten rock (called lava or magma) cools and hardens. Granite is an example of an igneous rock.Limestone
Another sedimentary stone, it's formed from calcite and sediment and comes in many earthen colors.Manufactured Stone / Agglomerate Stone
This is a synthetic stone made from natural stone chips suspended in a binder such as cement, epoxy resins or polyester.
Some of the most popular types of manufactured stone products are those made mostly of quartz. The natural quartz gives the product
depth and radiance while at the same time strength and consistency. Manufactured Stone is strong, it has four times the flexural
strength of granite, so there's less chance of chipping or cracking. It's also called Agglomerate Stone. The most well known agglomerated
stone is poured-in-place terrazzo, used in building for thousands of years.Marble
A derivative of limestone. It is a metamorphic stone that can be polished. Marble is characteristically soft and easily scratched or
etched by acids. There are countless types of marble from around the world.Metamorphic Rock
Created when other kinds of rocks are changed by great heat and pressure inside the earth. Marble, slate and quartzite are examples of
metamorphic rocks.Polished Surface
Finish A polished surface creates a beautiful glossy shine from the natural reflection of the stone's crystals. The mirror-like shine is
accomplished by using progressively finer polishing heads during the polishing process, similar to the way that sandpaper smoothes hardwood
furniture.Porosity
The amount and size of the pores in a stone. Travertine is very porous and granite is not.Quarry
For millions of years, a combination of heat and pressure created blocks of natural stone, including granite, marble, travertine, limestone,
and slate. As the earth's crust began to grow and erode, it pushed minerals up from its core, forming massive rock deposits, which we refer
to as "quarries".Sandstone
A sedimentary stone that is primarily composed of loose grains of quartz sand that are rough in texture. A number of varieties are available.Saw-Cut Refined Finish
Saw-cut refined offers a matte finish. After initial cutting, the stone is processed to remove the heaviest saw marks but not enough to achieve a
honed finish. You can purchase granite, marble and limestone this way, typically on a special order basis.Sedimentary Rock
Formed from deposits that have undergone consolidation and crystallization. Limestone and sandstone fall into this category.Slab
Blocks of stone that have been extracted from the earth and cut.Slate
A metamorphic stone that has a sheet-like structure. It is composed of clay, quartz and shale, and comes in a multitude of colors including reds
and greens.Split Faced Finish
Split-faced gives you a rough texture, but one not as abrasive as flamed. This finish is typically achieved by hand cutting and chiseling at the quarry,
exposing the natural cleft of the stone. This finish is primarily done on slate.Stone Tile
The typical natural stone floor tile sizes are 12"x12", 13"x13", 16"x16" and 18"x18".Straight 90-Degree Edge
One of two types of edges for natural stone floor tile. A polished straight 90- degree edge creates a more modern and clean look.Substrate
The surface on which the stone tile is laid.Thinset
A cement based adhesive that is applied to the surface with a notched or grooved trowel. The tile is then placed into the thinset and pressed firmly
into place. Since stone tiles vary in thickness and size, the amount of thinset mortar applied is adjusted where needed.Travertine
A crystallized, partially metamorphosed limestone which, because of its structure, can be filled and honed and is dense enough to be a type of
marble.Tumbled Finish
Delivers a smooth or slightly pitted surface, and broken, rounded edges and corners. There are several methods used to achieve the tumbled look.
3/8" thick tiles can be tumbled in a machine to achieve the desired look, or 3cm tiles can be tumbled and then split, creating two tiles that are tumbled
on one side. Marble and limestone are primary candidates for a tumbled finish.Unsanded Grout
A dry, Portland cement-based product that is mixed with water onsite. The grout mixture is spread over the tiled area with a grout float to fill in all the joints.
A sponge is then used to remove excess grout from the surface of the tile while leaving the grout in the joints to cure. Un-sanded grout is most commonly
used in natural stone installations because it is able to fill the small joints more easily and will not scratch soft stones like sanded grout.These articles are licensed under the GNU Free Documentation License. Most of the material on this page is from the Wikipedia the free encyclopedia.