UNIVERSITYOF SANTO TOMASCOLLEGE OF ARCHITECTUREEspañaBlvd, Sampaloc, Manila, Metro Manila, Philippines NATURAL SCIENCES 202: CORPUZ, ANGELICA CAMILLE V.3 AR-8AR. PINLACNATURAL SCIENCES 202 THREE CLASSIFICATIONSOF ROCKSEXAMPLES OF IGNEOUSROCKSGRANITELocation: Consideredas one of the most abundant rock found on the earth’s crust. Usually found inmountain ranges within large areas (batholiths) and core areas of continents(shields). Composition: Composedmainly of quartz and feldspar with small amounts of mica, amphiboles, and otherminerals.Strengths: Elegant,durable, long-lastingWeaknesses: Costs morethan man-made materials.Aesthetics: Light-coloredrock, usually of color red, pink, gray, or white, that has large, dark, mineralgrains.
Used for: Flooring,wall paneling, column, mullion facing, stair treads, flagstone, counter tops,bridges, paving, monuments, crushed stone or aggregateSERPENTINELocation: Found inareas near present or ancient convergent plate boundaries with exposed oceanicplates (ophiolites).Composition: It is agroup of minerals which are primarily composed of chrysotile, antigorite, andlizardite.Strengths: Easy towork with, fibrous, ability to resist heat and may be polished until lustrous,softer than granite but harder than marble which is appropriate to use forsurfaces that will not be exposed to abrasion.Weaknesses: May possiblycontain asbestos which is a very harmful chemical.Aesthetics: It isoften green but can also be color yellow, black, white, and other colors, has anattractive patterned appearance, and a slippery, greasy, waxy feel.
Comes fromthe word “serpent” because of its serpent-like characteristics.Used for: Exclusively used for interiors such as walland ceiling tiles, flooring, shingles, facing, stoves, pipe insulation, etc. dueto weathering.
BASALT ROCKLocation: Mostlyfound within the ocean basins such as oceanic divergent boundaries (Iceland),oceanic hotspots (Hawaiian Islands), and mantle plumes and hotspots beneathcontinents (Columbia River Flood Basalts in Washington, Oregon, and Idaho),considered to be the most abundant bedrock. Also found in the moon and mars.Composition: Composedof plagioclase and pyroxene mineralsStrengths:Has greatchemical resistance, high tensile strength, recyclable, processing does not requirespecial equipment or technologyWeaknesses: Abit expensive.Aesthetics: Dark-colored,fine-grainedUsed for: Road base,concrete aggregate, asphalt pavement, filter stone, floor tiles, buildingveneer, monuments EXAMPLES OF METAMORPHICROCKSMARBLELocation: Formed atconvergent plate boundaries where the crust of the earth is exposed to regionalmetamorphism.Composition: Mainly composedof calcite and other minerals such as clay, micas, quartz, pyrite, iron oxides,and graphite.Strengths: Easy tocarve and may be polished to a higher luster.Weaknesses: Quite expensive,heavy, high maintenance, not suitable for high traffic because it may lose itsshineAesthetics: Light-coloredrock may be white, bluish gray, pink, yellow, or black.
Used for: Flooring,wall and column facing, window sills, stair treads, columns, crushed stoneaggregateSLATE ROCKLocation: Found inthe convergent plate boundaries.Composition: Primarily composedof clay minerals or micas and may contain quartz and sprinkles of feldspar,calcite, pyrite, hematite, and other minerals.Strengths: Durableand attractive, can be cut into thin sheets, absorbs minimal moisture, goodelectrical insulatorWeaknesses: Costly andhas a trickier installation when used for roofing.Aesthetics: Mostlyseen in the shades of gray but may be produced in the colors green, red, black,purple, and brown depending on the amount of iron and organic material present.Used for: Tile flooring,backsplashes, table tops, window sills, stools, stair treads, roofing, andfacing GNEISSLocation: Found inconvergent plate boundariesComposition: Has bandsof feldspar and quartz grains. May contain biotite, cordierite, sillimanite,kyanite, staurolite, andalusite, and garnet.Strengths: Does notsplit along planes, durable, accepts bright polish, attractive, quality andaffordable stoneWeaknesses: Flakesmay come off from their rough surface.
Aesthetics: Light-coloredwith bands of dark-colored mineralsUsed for: Floortiles, facing, stair treads, window sills, countertops EXAMPLES OF SEDIMENTARYROCKSLIMESTONELocation: Found inclear, warm, shallow marine waters or in some lakes or ocean water.Composition: Composedof at least 50% calcium carbonate with a few percentages of quartz, feldspar,clay minerals, pyrite, siderite, and other minerals.Strengths: Strong anddense rocks with few pore spaces, able to withstand abrasion and freeze-thaw, easyto mine, low maintenanceWeaknesses: Expensive,complex installation, slippery when wetAesthetics: It hasdifferent varieties. It may be fine-grained and light-colored, poorly-cemented,has obvious and abundant fossils, some have very fine and uniform grain size,etc.Used for: Wall and floorsurfaces, stair treads, window sills, roofing granules, Portland cementTRAVERTINELocation: Usuallyfound in rivers and springs.
Composition: Composedof calcium carbonate.Strengths:May bepolished to a smooth and shiny finish, most frequently used stone, cheaper thanmarble and granite, very durable, environment friendly, easy installation, hasa wide range of colors to choose fromWeaknesses: Veryporous, reactive to acidic substances, heavierAesthetics: Comesin a wide range of colors from grey to coral-redUsed for: Interiorand exterior walls, floors and mosaic tiles BRECCIALocation: Commonlyfound at the base of an outcrop, stream deposits, or on an alluvial fan.Composition: Composedof rock and mineral materials.
Strengths: May beused for construction as aggregates.Weaknesses: Rarelyused in important projects because of the rock’s composition, degree ofcementation, and competence.Aesthetics: Is acolorful rock that has large and angular particles with the small gaps filledin with mineral cement.
Used for: Fill orroad base REFERENCESKing, H. M., Ph.D. (n.
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(n.d.). Basalt. Retrieved January 28, 2018, from https://geology.com/rocks/basalt.
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Marble. Retrieved January 28, 2018, from https://geology.com/rocks/marble.shtmlKing, H. M., Ph.D.
(n.d.). Slate. Retrieved January 28, 2018, from https://geology.com/rocks/slate.shtmlKing, H. M.
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Gneiss. Retrieved January 28, 2018, from https://geology.com/rocks/gneiss.
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Breccia. Retrieved January 28, 2018, from https://geology.com/rocks/breccia.shtmlThe Editors of Encyclopædia Britannica. (2011, April 08).
Travertine.Retrieved January 28, 2018, from https://www.britannica.com/science/travertineRamya S, — Follow.
(2016, August 24). Natural & Artificial stones& its uses in designing. Retrieved January28, 2018, from https://www.slideshare.net/RamyaS51/stones-presentation-ramya-2-65306367All photos courtesy of Google Photos