Product KnowledgeTraining GuideStone Products
♦ What are the differences in products •Granite •Marble •Travertine •Slate •Onyx •Limestone
♦ Applications and uses
♦ Care and maintenance
♦ Glossary of terms
♦ Selling Tips
Contents
Granite is an igneous rock, which was formed by slowly cooling pockets of magma (hot liquid) that was trapped beneath the earth’s surface. It is the result of about 570 million years in the making.
Granite is an intrusive rock – it forms deep underground and consists of mainly feldspar and quartz. Granite is the hardest known material used in commercial and residential applications.
Normally granite is classified in three different groups:
•FINEGRAIN:Finegraingranitesarethoseinwhichthefeldspar crystalsaverageabout1/16”-1/8"indiameter.
•MEDIUMGRAIN:Mediumgraingranitesarethoseinwhichthe feldsparcrystalsaverageabout1/4"indiameter.
•COARSEGRAIN:Coarsegraingranitesarethoseinwhichfeldspar crystalsaverage1/2",andgreaterdiameterorseveralcentimeters inmaximumdimension.Coarsegraingranitesmayhavealower density.
To Identify Granite: •Moregranularinappearancethatcaneasilybedistinguished •Courseandrelativelyconsistentappearance •Densewithminimalpores •Generallyminimalvariationbetweentilesorslabs
Common Finishes: •Polished,honed,flamed
Facts: •6.6–8.5onMOHShardnessscale–verydurable •Weatherresistant •Crystalscanbeviewedwiththenakedeye
Applications and uses: •Granitecanbeusedanywhere:interior/exterior,counters,walls, fireplaces,showers/tubs/vanities,flooringandfountains. •Commercialapplications:exteriorcladding,steps,heavytraffic areas,sidewalks.
Granite
Marble is formed from limestone by heat and pressure in the earth’s crust. These forces cause the limestone to change in texture and makeup.
Marble is a metamorphic rock, which means, “changed form”. This process took well over 540 million years. Marble is mostly made up of calcite – a mineral form of calcium carbonate. The purest calcite marble iswhite. The minerals that result from impurities is what gives marble such a wide variety of colors.
To Identify Marble: •Distinguishedveiningandcrystallization •Largetiletotilevariation •Extensivecolorpalette–fromwhitetoblack
Common Finishes: •Polished,honed,tumbled
Facts: •2.2–5.5onMOHShardnessscale;relativelysoft •Greenandblackmarblesshouldnotbeinstalledinwaterareas •Notrecommendedforfoodserviceapplications •Polishwillnotsustainifinstalledinanexteriorapplication
Applications and uses: •Marblecanbeusedoninteriorapplicationsforwalls,fireplaces, shower/tub/vanitiesandflooring. •Commercialapplications:interiorwalls,statues,heavytraffic flooring(withregularmaintenancetomaintainpolish).
Marble
Marble
Marble Classification
TheMarbleSoundnessClassificationsindicatewhatmethodandamountofrepairandfabricationarenecessarypriortoorduringinstallation,asbasedonstandardtradepractices.Theterms:waxing(1),sticking(2),andfilling(3)arecommonindustryterms:
(1) Waxing –Waxingreferstothepracticeoffillingminorsurfaceimperfections suchasvoidsorsandholeswithmeltedshellac,cabinetmaker’swaxorcertainpolyestercompounds.Itdoesnotrefertotheapplicationofpastewaxtomakesurfacesshinier.
(2) Sticking–Stickingdescribesthebuttedgerepairofabrokenpiece,nowgenerallydonewithdowels,cements,orepoxies.Thepiecesare“stuck”together;thus“sticking.”
(3) Filling–Fillingreferstotheprocessoffillinganysurfacevoidswithepoxy, cement,orresin.Fillingisnotintendedtobenoticeabletoagreatdegree, perfectlycolormatched,or“glass”smooth.
(4) Dry Vein-Dryveinsarefrequentlymistakenlythoughtbyconsumerstobecracksorunnaturallyoccurringbreaksinthestone.DryVeinsaredescribed whenanaturallyoccurringveinshowsaseparationbetweenthedifferentmaterials.
(5) Fissures-Fissuresarehairlinecracksorgroovesandareusuallycausedbyoxidationofthestone.Theytypicallydonotaffectthesoundnessofthestone.
Soundness Group A (MIA 11.5.1)-Soundmarbleswithuniformandfavorable workingqualities:containingfewgeologicalflawsorvoids,andsubtleandconsistentveining.Theyincludecompletelymetamorphosedlimestoneordolostone,inwhichimpuritiessuchasclaysandsilthavereactedchemically withthecalciteordolomitetoformotherminerals.Thesestoneshaveuniformworkingqualities,canbeusedontheexteriororinterior,anddonotrequireanyfillingorpatching.
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Soundness Group B (MIA 11.5.2)-MarblessimilarincharactertoGroupA,exceptthatalltheimpuritieshavenotchangedintootherminerals.Occasionalsmallholesandvoidsaretobeexpected,andarecharacteristicsofthisgroupofmarbles.Theholesorvoidsarefilledbythefactorywithepoxy,shellac,orpolyesterresin.ClassBmaybeusedontheexteriororinterior.
Soundness Group C (MIA 11.5.3)-Marbleswithsomevariationsinworkingqualities. Geologicalflaws,voids,veins,andlinesofseparationarecommon.Manyoftheimpuritieshavenotchangedintootherminerals,andmetamorphosisisnotcomplete.Thisisthelargestandmostcolorfulgroupofmarbles,andalsocontainssignificantholes,voids,linesofseparation,andstructuralflaws.Itisstandardpracticetorepairthesevariationsbyuseofreinforcing,liners,stickingtogether,fillingwithresinorcement,fabricatingcornersormissingstonewithterrazzoandresin,anddoingallotherworknecessarytoholdthestonetogethertoyieldafinishedproductthatisusableforarchitecturalpurposes.Oncompletion,mostrepairsarevisibleandapparent,withadifferenceinlightreflection.Theycontainmesh,resin,epoxy,orfiberglassbacking.Withfewexceptions,thesemarblesarenotsuitableforexteriorinstallation.
SoundnessGroupD(MIA11.5.4)-Marblessimilartotheprecedinggroup,butcon-tainingalargerproportionofnaturalfaults,maximumvariationsinworkingqualities, andrequiringmoreofthesamemethodsoffinishing.Fewstonescarrythisdesignation atthistime;itisreservedforverylaboriousGroupCstones.
Special Notes
Green MarblesGreenmarblesarenotrecommendedforwetareasofyourhome,andtheyarenotrecommendedtobeusedwithwaterbasedadhesivesduringinstallation.Becauseoftheuniquemineralcontentinthesemarbles,thetileswillabsorbthewaterandmayhaveatendencytocurlorwarp.Withthisdynamicinmind,theonlywaytopreventissuesistoinstallitproperlywithanon-waterbasedmaterialsuchasepoxy.
Resin Back MarblesTheresinbackingsaredesignedtoproviderigidityandtostabilizesomeofthemore fragilestonetypesusedonfloors.Thesebackingscanbecomposedofpolyester,urethaneorepoxy.Somebackingscanincludefiber-meshscrims.Thebestresultscomefrominstallingresin-backedstoneswithanepoxy-basedadhesive.
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Marble
Slate is a metamorphic rock. Most slate is formed below the earth’s surface by changes in the makeup and appearance of shale, which is a sedimentary rock. Shale consists of clay and fine particles of quartz.
Heat from deep in the earth changes some of the clay in shale into mica and chlorite. Slate results when pressure created chiefly by mountain-forming movements in the earth’s crust squeezes the mica and other minerals into parallel layers.
To Identify Slate: •Commoncolors:fromgraysandblackstorustsandgreens (manyslatesaremulti-colored) •Largetiletotilecolorandsurfacevariation •Slatehasalayeredappearance
Common Finishes: •Naturalcleft,gauged,ungauged,tumbled,honed,polished
Facts: •6.0onMOHShardnessscale;verydurable •Shaling(piecesfallingoffface)iscommonwithinthefirst6months ofinstallation •Madeupofmostlyclayandshale(siltandclay);verydense
Applications and uses: •Slatecanbeusedininteriorandexteriorapplications:walls, fireplaces,showers/tubs/vanities,flooring,fountainsand backsplashes. •Commercialapplications:roofing,exterior/interiorcladding,trim accentsandsomeflooringapplications.
Slate
Slate - Interior Applications
CharacteristicsIntheindustrytherearevariousstonesthatgobythename“slate”,someofwhichincludequartzite,shale,andschist.Althoughsimilarinappearance,theserocksvaryintheirformation,mineralcontent,andtheiradvisedapplications.
Mostvarietiesofslaterepresentawidespectrumofcolors.Duetothishighvariation,notwotilesarealikeandthestonewillvaryfrombatchtobatch.Itisimpracticaltoattempthandselectingthecolors.Tilesthatwerecutoutofthesameblockmayconsistofsolidcolorsfromoppositeendsofthespectrumandmaycontaininfinitecombinationsofmovement.
FlakingSlateisafoliatedrock.Thelayerswillhaveatendencytoflakepostinstallationasthestonesettles.Notonlyistherepotentialforadditionalcolorsofthestonetobeexposedasalayercleavesoff,butthetexturemayalsochangeasaresult.Thisisnotadefectofthestone,andeventuallytheflakingwillstop.Whenusedinwetapplicationswheredrainsarepresent,itisrecommendedthatafinenetbeplacedinthedraintocatchthepiecesofrockduringthesettlingprocess.
RustItisnotuncommontoseerustappearonslateasaresultofironandothermineralswithinthestoneoxidizingfrommoisture.Oxidationisaninherentcharacteristicofmanystonesandmustnotbeleftuntreated,asitmaycausethestonetobecomebrittleovertime.Properuseofsealersaswellasawaterproofingmembraneonthesubstratewillpreventthisfromhappening.
AbsorptionSlate’sabsorptionratecanbeaslowas.2%,whichisoftenseeninslaterooftiles.Somevariations;however,canbeasabsorbentas10%.Theabsorptionratewillvarybetweendifferenttypesofslate.Evenwithalowabsorptionrate,watermaystillpenetratethesurfaceandcompromisethestones’stability.Waterwillfinditswaythroughanycrackorcrevicewhichpotentiallywillcausethestonetoswell.Thistypeofswellinginslateswillalsomakethembrittleandmayevenweakenthetile’sbondtothesubstrate.Itishighlyrecommendedthatstonesbesealedtopreventanytypeofwaterdamage.Thesechemicalsealersmayneedtobereappliedbasedonthemanufacturer’sinstructionstoensurethelongevityofyourtile.
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Slate
Slate - Exterior Applications
CharacteristicsSlateisametamorphic,foliatedrockcomprisedofvariouslayersofmud,mineralflakesandshale,whereasquartziteisnon-foliatedandistypicallyametamorphosis ofsandstone.Althoughatfirstglancethesestoneslooksimilar,theycarrydifferentcharacteristicsandattributesthatarecriticaltotheirapplications.
Theformationoftheserocksissignificantforanumberofreasons.Byunderstanding thatslateisfoliated,thelayerswillhaveatendencytoflakepostinstallationasthestonesettles.Notonlyistherepotentialforadditionalcolorsofthestonetobeexposed asalayercleavesoff,butasaresultthetexturemayalsochange.Thisisnotadefectofthestone,andeventuallytheflakingwillstop.Quartziteontheotherhandwillbemoreconsistentincolorandtexturesinceitisnotformedinthesametypeoflayersandwillnotgothroughthesamesettlingprocesspostinstallation.
Freeze / Thaw Climates and WeatheringAlthoughslatesareratedforexterioruse,notallofthemarefreeze/thawrated.Infreeze/thawclimates,whenwaterpenetratesthesurfaceofastoneandfreezesover,thereisariskofthetileshattering.Whenwaterfreezes,itexpandsbyapproximately 9%.Asthisexpansionisresisted,thepressureexertedcanbeupto150tonspersquarefoot.Thistypeofpressureissufficienttospliteventhestrongestrocks.Because slateisafoliatedstone,thesplittingwillbeunpredictable,andwilllikelybreakapartinrandomsegments.
InstallationAsidefromslate’snaturalporouscharacteristics,otherfactorsaffectwaterretention inthestone.Ifslateisnotinstalledusingtheproperwaterproofingmembranesinanexteriorapplication,waterwillfinditswaythroughanycracksorcreviceswhichpotentiallywillcausethestonetoswell.Thistypeofswellinginslatewillalsomakethembrittleandmayevenweakenthetile’sbondtothesubstrate.Flakingcanbemagnifiedasaresultofsuchswelling.
Appropriatemeasuresmustbetakentoinstallastoneofthisnatureinanyexteriorapplication.Therearevarioussealersonthemarketaswellaswaterproofingmembranesthatwilloffsetanynegativeeffectstheweathermayhaveonslate.Thesechemicalsealersmayneedtobereappliedbasedonthemanufacturer’sinstructionstoensurethelongevityofthetile.
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Slate
Limestone is comprised chiefly of calcite, a mineral form of calcium carbonate. It is also sometimes referred to as a ‘young’ marble. Limestone was formed over many years (320 million) at the bottom of oceans and lakes, which designates it as a sedimentary stone. Limestones consist of an accumulation of shells, bones, and other calcium rich goods.
Limestone is divided into three sub-classifications that describe their densities in approximate ranges, as follows:
•LOW DENSITY-Limestonehavingadensityrangingfrom110 through135/lb/ft3(1760through2160kg/m3). •MEDIUM DENSITY-Limestonehavingadensitygreaterthat135 andnotgreaterthan160lb/ft3(2160through2560kg/m3). •HIGH DENSITY-Limestonehavingadensitygreaterthan160lb/ft3 (2560kg/m3).
Limestone contains a number of distinguishable natural characteristics, including calcite streaks or spots, fossils or shell formations, pit holes, reedy formations, open texture streaks, honeycomb formations, iron spots, travertine -like formations and grain formation changes. One or a combination of these characteristics will affect the texture.
To Identify Limestone: •Commoncolors–beige,gray,white–fairlyneutralincolor •Fairlyconsistenttiletotilevariation •Tight-grainedappearance
Common Finishes: •Honed,polished,sandblasted
Facts: •3.0–4.0onMOHShardnessscale–verysoft •Limestonemakesanexcellentbuildingstone–itcanbecarvedeasily •Ifshellfossilsarestillvisible(althoughpolished),itisconsidereda limestonenotamarble
Applications and uses: •Limestonecanbeusedininteriorandsomeexteriorapplications: walls,fireplaces,showers/tubs/vanities,flooring. •Commercialapplications:interiorandsomeexteriorcladding,flooring.
Limestone
Travertine is limestone that has been evolved and formed over a longer period of time. The product is porous with many visible holes. Travertine is available in colors ranging from ivory to golden brown. The holes and cavities may be filled with matching Portland cement, colored epoxy, or polyester resins. Travertine is a sedimentary, calciferous stone formed in hot springs. Typically, hot water passes through limestone beds, taking the calcium from the limestone into suspension and bringing that solution to the surface. The water then evaporates and leaves the calcium crystals in layers on the surface.
To Identify Travertine: •Holesorcavitiesvisibleinstone–filledorunfilled •Producedwitheithera“veincut”(horizontalveins)ora“crosscut” (flowerypattern) •Quarriednearhotsprings
Common Finishes: •Honed,polished,tumbled,filled,unfilled
Facts: •3.0–5.5onMOHShardnessscale–moderatestrength •TheColiseuminRomeismadeoftravertine •Unfilledgivesarusticappearancewhilefilledgivesamoreformallook
Applications and uses: •Travertinecanbeusedininteriorandexteriorapplications:walls, fireplaces,showers/tubs/vanities,flooring,andbacksplashes. •Commercialapplications:interiorandsomeexteriorcladding, flooring.
Travertine
Travertine
Special Notes
Withinthefirst12-18monthsofinstallationofafilledandhonedtravertine floor,itisnormaltoexpect5–10%ofthefloortoexperienceexposureofnewholes,particularlyinhightrafficareas.
Thisoccursduetothenatureoftravertineitselfasitisacapillaryfilledstone.Whenthetilesgoalongthefillingline,themachinewillfillallthevisibleholes,pitsandfissuresonthesurfacepriortopolishing.Duringinstallationandthesettlingprocesspostinstallation,itiscommonforfoottraffic,furniture,etc.toexposethesevoidsorloosenthefillers.Thiswillbevisibleinhightrafficareasandisnormalandexpectedwithallfilledstones.
Toremedythisissue,itisbesttowaitatleast12monthsformostoftheshallowporestoexposethemselves.Atthistime,cleanoutanyloosedebrisintheexposedarea.Donotdigorsticksharpinstrumentsintothehole,asitwillexaggeratetheproblemandpossiblyopenupadditionalholesthanwouldnotoccurnormallywithnaturalfoottraffic.Makesuretheareaaroundthevoidisrepairedandsealedwellastonotallowanynewgrouttoadheretothestone’ssurface.Filltheholeswithregularsandedorepoxygrout(whatevercolorisdeemedappropriatetomatchthestone).Afterthisapplicationiscompleted,makesurethesenewlygroutedareasaresealedwithanyregularnon-solventbasedstonesealer.
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Onyx is a translucent stone with a layered appearance.
Onyx is similar to travertine, as it is formed as a result of cold solutions of carbonated water dissolving existing stone and re-depositing it into a new stone. The term “onyx” to designate onyx marble is a misnomer. True onyx (silicon dioxide) is a semi-precious stone.
To Identify Granite: •Translucentinappearance •Commoncolors–jadegreen,warmhoneytones,andreds •Verylargetiletotilevariation
Common Finishes: •Polished,tumbled
Facts: •Verysoftandbrittle •Scratcheseasily •Beautifulwhenlightingisinstalledbehindthestone
Applications and uses: •Onyxcanbeinstalledinbathroomsandlowtrafficareas. •Commercialapplications:bartops,verticalcladding.
Onyx
The Moh’s hardness scale was created to measure the hardness of minerals. The scale starts with the softest mineral (talc), and progresses to the hardest (diamond). The only thing that can scratch a diamond is itself.
Hardness and specific gravity are two of the major characteristics of rocks. Hardness of a rock or mineral is defined by its resistance to scratching and may be described relative to a standard scale of 10 minerals known as the Mohs Scale.
F. Mohs, an Austrian mineralogist, developed this scale in 1822. Specific gravity is the number of times heavier a gemstone of any volume is than an equal volume of water. In other words, it is the ratio of the density of the gemstone to the density of water.
General Information
General Information
Variationinveining,fissures,pits,texture,color,andshadeisaninherentcharacteristicofallnaturalstones.Thesevariationsaretobeexpectedfromtiletotileaswellasfromlottolot,dependingonthetypeofstonethatisselected.
SomespeciesandcolorsaremoreconsistentthanothersandwillrangefromV0-V5shadevariation.Handselectingcolorsisnotpracticalfornaturalstones,althoughrangesamplescanberequestedtorepresentthecurrentlotpriortopurchasing.
Preventive Measures against Shade VariationItisimportanttoinspectalltilespriortoinstallation.Subtlevariationsbetweenadarkerandlightershadecanusuallybehiddenwhenthedarkershadeisputaroundtheperimeteroftheroomandthelightershadesareusedinthemiddle oftheroomtoavoidcreatingunwantedcontrastsorpatterns.
Duringproductinspection,tilesthatarequestionableorunusableshouldbesetaside.Itisalsoimportanttocalculateproperoveragewhenpurchasing(usually20%),asanallowanceforwastefromcutsandcolorvariation.Professional installerswillpullfrommultipleboxestohelpblendthenaturalvariationbetween tiles.
Grades of MarbleMarblesandothernaturalstonesarecategorizedbysoundnessclassifications:A-D.SomeCandDstonesaremanufacturedwithresinreinforcedmeshbacking, holesarefilledwithcementorepoxyandrodsareusedforstability.Veiningandcoloringcanbeinconsistent.Chippededgesandcornersarerepairedwithepoxy.
Somespeciesofstonehavemoreinconsistenciesthanothers;howeverthisisnotadefectofthestone.Itisindustrystandardaslongasitisgradedcorrectly.
Sealing GraniteAsageneralrule,itisimportanttosealallnaturalstones,evengranites.However,theonlystonethattypicallygoesunsealedisblackgranite.Whenusedascountertopsorinwetapplications,sealedblackgranitesareknowntoshowwatermarksandringswhenexposedtomoistureoracidsforextended periodsoftime.Thesewatermarksor“etching”canbecausedbyanumberoffactors:Themostcommonbeingareactionofthesealerbeingexposedtowaterforprolongedperiods.Anotherreasonmaybeareactionofthemineralonthesurfaceofthestonetoacids.Inbothcases,itisbesttocontactthesealermanufacturerforrecommendationsoncleaningthesespots.
Slate ExteriorsMostslatesarenotratedforexteriors,wetapplications,orfreeze/thawclimates. Slatescanswellinwetapplications,becomemuddy,becomebrittle,rust,flake,andfallapart.Itisimportanttoknowwheretheslateisbeinginstalledpriortorecommendingitforaparticularapplication.Quartzite,althoughitlookslikeslate,isacompletelydifferentrockanditcanbeusedinbothwetapplicationsandexteriorfreezethawclimates.
Epoxy Thin-setsItisimportanttouseepoxybased,solidsettingadhesivesandgroutswheninstallingmesh,resin,epoxy,orfiberglassbackedstonestoensureproperadhesion.Stonesrequiringepoxythinsets,eveniftheyarenotmesh-backedare:greenmarbles,blackmarbles,andsomevarietiesofsandstones.Thesestonestypicallywarporcanacquireefflorescencefrommoistureinastandard mortar/thin-set.
LippageLippageiscausedbyanumberoffactors:Unevensubfloors,notbackbutteringlargetiles,groutjointsthataretoonarrow,naturallightsourcemakingstandard variancesmorenoticeable,etc.Thefirstthingsinspectorswilllookforonalippageclaimisasoftjointaroundtheperimeteroftheapplication,variances inthetileaccountedforwiththepropergroutjointwidths,andproperoffsetpercentagesifabrickjointpatternwasused.
Recommended Off-Set for Brick Joint PatternsA33%maximumoff-setandpropergroutjointwidthisrecommendedtoprevent theappearanceoflippage.
A50%off-setonlargeformatsquareandrectangulartilesisnotrecommended, duetostandardmanufacturingtolerances.
General Information
Stone Maintenance & Care
All natural stone should been maintained properly. All finishes of stone – honed, polished or tumbled, look beautiful and are very durable when protected and maintained. Sealing all natural stone is highly recommended.
It is suggested that a breathable, penetrating sealer is applied. Aqua Mix as well Miracle Sealants provide different types of high quality penetrating sealers
Tips: •Sweeporvacuumfloorsregularly •Washwithclearwateroccasionally–ifsoapisused,itmustbe PHbalanced! •Neverusevinegaronnaturalstone •NeveruseanycleanersthatcontainACID •Protectstonefromsandandgrit–usedoormats •Usearag(string)mopversesaspongemop–dirtgetspushedinto thegroutjointswithaspongemop •Tendtospillsquickly.Goodsealersprovideawindowofafewseconds forcleanup.Sealers do not prevent 100% of damage due to spills.
Efflorescence, Rust, and Moisture Sensitive StonesAllstonesareporoustovaryingdegrees.Efflorescenceandrustcanbeacommonoccurrenceinnaturalstoneswhentheyareexposedtomoisture.Itisimportanttoidentifythesourceoftheproblembeforecleaningorreplacing thestone,astheseoccurrencescanbeinstallationrelated.
Efflorescenceisaconcentrationofsolublesalttrappedinthestonethatwillappearcloudyandwhite.Itiscommoninhotclimateswherethewaterescapesfromthestonequickly,leavingatraceofsaltclosertothesurface.Rustwillalsoappearwhenthemetalmineralsofcertaintypesofstonereactwithmoisture.Bothrustandefflorescencecanbecleanedusingwaterandamediumbristlebrush.Wherethedepositshavebeenpresentforawhile,alightmuriaticacidmixcanbeusedtocleanthesurfaceofthestone.
Itisimperativethatthestonebeproperlysealedaftercleaning.Properwaterproofingmembranesarerequiredwhereproductisexposedtoweatheringorisindirectcontactwithwater.Theuseofasealerishighlyrecommendedtoprotectthesurfaceofthestone.
Stone Maintenance & Care
Common Questions
Why is Granite preferred for kitchen / bar countertops?Countertopsinkitchensandbarareasareoftenexposedtoacidicsubstances suchaslemon,vinegar,alcohol,tomatosauce,etc.Knives,dishes,potsandpans,andotherimplementsmaycausescratchingofsoftermaterials.Granite isthehardestanddensestofallnaturalstones.Thefeldsparcontentkeepsitwaterresistant,andthesilicatesitcontainswon’treactwithacid.ThesepropertieshelpGraniteresiststainingandretainitsfinelusteroveralongerperiodoftimethanceramictilesorotherstones.AlthoughMarbleiscommonly requestedforcountertopsinbarsandkitchens,marble’shighcarbonatecontentmakesitvulnerabletoacidicsubstances.
Why are Limestone and Travertine preferred for family or living rooms?Thefamilyorlivingroominahomeisaplaceforpeaceandrelaxation,andthesoft,mutedtonesandtexturesoflimestoneortravertinearetheperfecttouch.Availableinshadesofbeige,tan,yellowandgoldandprocessedwithatumbledorantiquedtexture,limestonecomplementsalltypesoffurniture andupholstery.
Why is Marble preferred for bathrooms and fireplaces?Homeownersoftenenjoybathroomswithboldcolorsandsmooth,flowingpatterns.Marbleistheperfectchoiceforthisapplicationduetoitswidespectrumofavailablecolors.Italsolendsitselfwelltocarvedpatternsanddetails,creatingbothtraditionalandartisticdesigns.Whilekitchencountertops areoftenexposedtoacidicsubstances,bathroomcountertopsaremorelikelytobeexposedtoalkalineproducts,whichdonotreactwithMarble.
Why is Slate preferred for patios or atriums?Theearthtonesandrusticlookofslatecreateacomfortable,naturallookthatisrightathomewithexteriorlandscapingandinteriorgardendesigns.Slateisnaturallyslipresistant,evenwhenwet,andismuchlesslikelytoshowdustanddirtthanpolishedgraniteormarble.It’salsorelativelylowpriced,whichmakesitagreatchoiceforlarge,informalareas.
Where do natural stones come from?Naturalstonesarequarrieddirectlyfromtheearth’scrust,andeverypieceisunique.Theonlyprocessingtheyneedisshapingintovariousforms,sizesandfinishes.
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Stone Maintenance & Care
Why are most natural stones imported?Sourcesofnaturalstonewithdesirablequalitiesarefoundallovertheworldinmanydifferentlocations.Somesourcesarepreferabletoothers,duetothestones’appearance,hardness,andotherqualities.Therefore,stonemaybequarriedinChina,India,Africa,SouthAmerica,EuropeandNorthAmerica.Costofprocessingisalsoafactor.Sincenaturalstonehasbeenusedasabuildingmaterialforthousandsofyearsinmanylocationsoverseas,thoseareas havealong-establishedsystemforquarryingandprocessingthesestoneswhichisefficientandeconomical.
What is the quality difference in stone from different countries?Naturalstonefromdifferentareascontainsavariedmixofmineraldeposits androckformations.Forexample,themineralMicamaybefoundmorefrequentlyinsomeareas,whichmeansthattherockfromthatlocationwillcontainbiggershinycrystalsthanwewouldfindinplaceswherelessMicaisfound.Somecountriesquarrymorelimestonethangranite.Therefore,stonefromcertainplacesmaybebettersuitedforoneapplicationthananother.Naturalstonequalitiesandcharacteristicsdifferduetogeologicalformations,notgeographicalboundaries.
Why some stones could not be used for exterior applications?Sometypesofstonearebettersuitedforinteriorapplicationsthanexteriorbecausetheyarenotabletowithstandharshweatherextremesandmaycrack,crumble,orfade.Also,stoneswithnaturallyslip-resistantsurfacesarebetterforoutdoorwalkwaysorpatiosthanthosewithsmooth,polishedsurfaces. Somemulticoloredslatesbleedcoloruponcontactwithwater.
How to install resin-backed stone products?Insomecasestheremaybeawaxy,slickbackingcoveringthemeshontheback(setting)sideofthestone.Thisiscommonwiththinstonesorthosewithalotofveiningand/orfissures.Whilethestonewithouttheresinbackingmakesforastraightforwardinstallation,somevarietiesofstonesaretoothinand/orfragiletowithstandtherigorsofhandlingpriortobeinginstalled.
Types of Resins
Knowingthetypeofresinbackingonthestonecanhelptodetermineiftheadhesivemortarbeingusedisappropriate.Thesebackingscanbecomposedofpolyester,urethane,orepoxy.Somebackingscanincludefiber-meshscrims.Othersmayincludeanotherthinlycutstonelaminatedtothebackofanotherstone.Thebackingsaredesignedtoproviderigidityandtostabilizesomeofthemorefragilestonetypesusedonfloors.
Somestonemanufacturerswillbroadcastsharpsandorotheraggregateintotheresintofacilitatebettermechanicalgriporadhesiontothemortar.Whenthisisthecase,alatex-modifiedmortarmaybeused.Thetypeofresinusedcanalsoinfluencetheadhesivethatisused.Keepinmindthattheremaybecount-lesstypesandvaryingqualityofresinsusedonthebacksofthesestones.Despite thisfact,therearethreemainfamilytypesthattheseresinsfallinto:polyester,epoxyandurethane.
Thepolyestertypescanbesomewhatproblematic.Theyarethemostcommon, sincetheyarethemostinexpensivetype.Polyesterresinisgenerallyacoldappliedmaterialthatispouredorrolledontothebackofthestone.Asithardens,awaxyfilmdevelopsonthesurfaceoftheresin.Thisveryslickmaterialpresentsadauntingproblemformostlatexthin-setmortars.Therefore,itisbesttouseanepoxyadhesiveforthesetypesofresinbackings.
Epoxyresinmeshesareofbetterqualitythanpolyestermeshes,howeverlatexthin-setmortarswillhaveahardtimebondingtoepoxyresins.Theepoxyresinsaregenerallyatwo-partproductmadeupofoneparthardenerandonepartresin.Thismaterialisgenerallycoldapplied,butreliesonchemicalreactiontocureoutandharden.Epoxyadhesivesarethepreferredchoicetoinstallthesestones.
Urethanebackingsareprobablythetypethatisleastcommonlyused.Epoxyadhesivesarealsobethebestchoicetouseforurethanemeshes.
Aninterestingfactisthattherearecurrentlynostandardstodeterminewhattheminimumbondstrengthoftheresinbackingtotheactualstoneshouldbe.Thisleavesaninstallerwiththeunfortunatetaskoftryingtodetermineifthestoneandbackingaresuitable.
Thereisanotherareaofconcernwhenitcomestoinstallingthesestonesthatshouldbeconsidered.Itisimportanttovalidatethebondstrengthoftheresinmeshtothebackofthestone.Ifitiseasytoremovethisbacking,itwillbeofnousetoinstallthestone,asitisaprojectfailurewaitingtohappen.
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Stone Maintenance & Care
Stone - Glossary of Terms
Breathing:Theabilityofastonetoexpandandcontractaswellastoallowevaporationofmoisture.
Chip:Asmallpieceofastonethatcanbereplaced(orrepaired)withepoxyresinorfilledwithcrushedchipsandepoxy.
Density:Theclosenessoftheparticlesinthematerial.Granite,forInstanceismoredensethanmarble;therefore,itisharder,heavier,andlessporous.
Etch:Alsoknownasacidburn.Theconditionwherebyacidorstrongalkalinehasdissolvedaportionofthestone.
Epoxy:Atwo-partresinglueusedforjoiningandfillingstone.
Fissures:Naturalhairlinefractures.Whenthestonewasgoingthroughthemetamorphicchangeswithheatandpressuretherewereveinsofsiltanddirtcollectedthathavesincedisappeared.
Flamed Finish:Flamedfinishisusedongranite.Thesurfaceisflamedwithacetylenetorchuntiltheweakpartofthestoneseparatesinanirregularpattern.Theresultisnon-reflective,textured,durableandslip-resistantsurface.
Fleuri Cut:Alsoknownascross-cut.Typicallyusedwithtravertine.Itrevealsaflower-likepattern.Ablockofstoneiscutonthebiastocreateanewsurfacelook.
Honed Finish:Thisfinishcreatesasmooth,butnotpolished,surface.Thesamepolishingstonethatcancreateahighglossareusedbuttheprocessisstoppedpriortoashine.
Stone - Glossary of Terms
Grout:Groutconsistsofcement,hardeners,andcolorsorepoxyandcolors.Itisusedinafluidstatetofillthespacebetweentilesorjointsandallowedtoharden.Groutactslikeashockabsorberbetweentilesorstones.Acementgroutcomesintwoversions–sandedforgroutjointsover1/8”andunsandedforanythingelse.
Igneous:Graniteisanigneousrockwhichmeansitwasoncemoltenandformedasitcooleddeepwithintheearth.
Intrusive:Graniteisanintrusiverock–founddeepwithinthemantleofavolcano;whereas, lavaisanextrusiverock–spewedforthfromthevolcano.
Polish:Theshinysurfaceofastone.Thepolishingprocessandspecialbuffingcompounds achievethis.
Porosity:Referstotheamountandsizeortheporesinastone.Travertineisextremelyporous.Graniteisnotveryporous.
Slab:Anaturalstoneslabispreliminaryusedforkitchencounters,vanitiesandcladding. Thecommonsizeis6’x8’withroughedges.Itisthenfabricatedtoadesiredsize.
Stone Tile:Naturalstonethathasbeencutdowntotypical;12”x12”orlarger16”x16”,18”x18”,24”x24”oramodularsize.
Spalling:Smallchunksthatbreakawayfromthefaceofastone.
Stone - Selling Tips
•Naturalstoneisaproductofnatureandisunique,beautiful,andaddspersonalitytotheenvironmentandisnotmeanttobeuniform,consistentorflawless.
•Thepriceofanaturalstoneproductisnotalwaysdirectlyrelatedtotheperceivedquality. -Pricecanbeimpactedbyavailabilityandorexchangeratesdueto thecountryoforigin.
•Don’tconfusequalitywiththestone’sinherentcharacteristics. -Voids,fissuresandfillarecommoninallnaturalstoneproducts.
•Naturalstonehasvariations.Viewingorsamplingonepieceofstonemaynotadequatelyrepresentthefullrangeorbeautyofaproduct.
•Apolishedstoneisnotasealedstone–thepolishedfinishismoreaestheticthanfunctional.Itisrecommendedtosealallstoneproductsafterinstallation.
•Greenmarbles–arenotrecommendedforwetareasbecause,likewood,theyabsorbwaterandwillcurlandwarp.Forotherareaswerecommendawater-freeepoxytosettheproductin.
•Blackmarbles–theyalsorespondtowaterbyspallingattheveinandthereforeshouldnotbeinstalledinwetareas.Forotherareaswerecommend awater-freeepoxytosettheproductin.