Natural Stone Tiles

[GazTech]

Natural stone has been used on walls and floors for thousands of years and continues to be a popular choice today due to its natural beauty,versatility and durability.There are many different types of natural stone each with its own characteristics.So because they are all different,I have compiled some useful information on what you are dealing with and the respect it should deserve.
GRANITE
The hardest and most durable of all natural stone products.It is an igneous material formed from molten lava.It is non calcareous and is resistant to acid based substances.Granite is the only true natural stone suitable to use as worktops,as it is much less porous than other natural stone.
SLATE
A very affordable metamorphic stone composed of silt,ore,shale and volcanic ash compressed over millions of years in the Earths sedimentary layers.Non calcareous and therefore resistant to acid substances.The minerals within give slate a rich variation of colours giving it an individual feel.
LIMESTONE
A warm material of sedimentary composition,formed by compaction of insoluable calcium salts and shelled sea creatures.It is calcareous and not resistant to acid substances,very porous.

MARBLE
A luxurious and sought after building material used in construction since pre-Roman times.A metamorphic limestone formed when rock is changed by exposure to extreme heat & pressue from volcanic action.The crystalline structure is hard and dense allowing it to be polished to a high gloss finish.Calcareous and therefore not resistant to acid and porus.
SANDSTONE
Used by ancient Egyptians to construct pyramids.A durable sedimentary stone created by the compaction of minute quartz grains and sand particles.Calcareous,not resistant to acid and very porous.
TRAVERTINE
Derived from marble,this sedimentary stone has been formed very slowly from the precipitation of calcite in the cooling waters around hot springs and underground rivers and caves.Calcareous,not resistant toacid based substances and porous.
TERRACOTTA
Made from clay,the Earth's most abundant natural building material.Highly porous and warm to the touch.It improves its patina with age and provides the Mediterranean look.Tiles are either hand made ( a centuries old tradition ) or machine produced.
ALL NATURAL PRODUCTS
All natural stone should be sealed to prevent staining,it is a misconception that a polished stone tile is sealed....wrong,the polishing process exposes microscopic holes in the surface that will fill with dirt given time,this is irriversable.All natural stone manufacturers will have a reccomended sealant.

[Home Tiler]

nice bit of info there ...cheers gaz!

[Dave]

Great thread gaz....should be very informative to newbies and tilers alike......dave..

[McP77]

Some good info there. Not wishing to be picky though but travertine is actually a limestone not a marble

[grumpygrouter]

Some good info there. Not wishing to be picky though but travertine is actually a limestone not a marble

Does limestone not change over the millenia through marble to granite then?

[McP77]

Limestone changes into marble yes but not to granite. Granite is naturally formed from molton lava.

[Dave]

Travertine is a sedimentary rock. Travertine is a natural chemical precipitate of carbonate minerals; typically aragonite, but often recrystallized to or primarily calcite; which is deposited from the water of mineral springs (especially hot springs) or streams saturated with calcium carbonate. When pure, travertine is white, but often is brown to yellow due to impurities. When carbon dioxide-rich water percolates through rocks in limestone areas, the water dissolves the limestone and becomes saturated with it. When the water resurfaces later, the sudden drop in pressure and the change in temperature cause the water to release the carbon dioxide gas, much like fizzy drinks. The calcium carbonate then recrystallizes, often over minute underwater plants. The resulting rock is typically quite porous with numerous cavities. When exceptionally porous it is known as calcarious tufa.
Travertine is one of several natural stones that are used for paving patios and garden paths. It is sometimes known as travertine limestone, sometimes as travertine marble; these are the same stone, even though it is neither limestone nor marble. The stone is characterised by pitted holes and troughs in its surface. Although these troughs occur naturally, they suggest to some eyes that considerable wear and tear has occurred over many years. Some installers use a grout to fill these holes, whereas others leave them open — travertine can even be purchased "filled" or "unfilled." It can be effectively polished to a smooth, shiny finish and comes in a variety of colors from grey to coral-red. Travertine is most commonly available

[GazTech]

Some good info there. Not wishing to be picky though but travertine is actually a limestone not a marble

Limestone,Travertine and Marble are all calcium carbonate,and very closely related CaCO3,very difficult to make a clear defenition between them, thanks McP77

[GazTech]

TRAVERTINE
Derived from marble,this sedimentary stone has been formed very slowly from the precipitation of calcite in the cooling waters around hot springs and underground rivers and caves.Calcareous,not resistant to acid based substances and porous.

[McP77]

Limestone,Travertine and Marble are all calcium carbonate,and very closely related CaCO3,very difficult to make a clear defenition between them, thanks McP77

You're not wrong there. I've looked into it a bit more and it's quite interesting. Apparently pure travertine is white and the colours come from impurities. Travertine is formed when carbon dioxide rich water goes through limestone and disolves the limestone. When this water resurfaces later the change in pressure and temperature causes the water to release the carbon dioxide and then recrystallises.

(sorry if this thread is getting geeky, I'm a closet wannabe)

[Dave]

hmmmm..interesting......lol...

[GazTech]

You're not wrong there. I've looked into it a bit more and it's quite interesting. Apparently pure travertine is white and the colours come from impurities. Travertine is formed when carbon dioxide rich water goes through limestone and disolves the limestone. When this water resurfaces later the change in pressure and temperature causes the water to release the carbon dioxide and then recrystallises.

(sorry if this thread is getting geeky, I'm a closet geologist wannabe)

Its great that you question things,we all need to trust the people giving us the information,thanks for your input mcp77

[McP77]

Yeah, I think we're reading the same article.

[GazTech]

I never took it from any article it was my own work lol

[CON5933]

Gentlemen, what an interesting and imformative post.... there are however some important facts missing which are pertinent to Natural Stone products...

allow me:

Marble, Granite, Travertine, Limestone, Slate, Terracotta etc etc
@ £35 to £40 per square metre + materials (dependant on location of course)

[IvegotsTILE]

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Your making me sleepy,very sleepy. lol

[brian c]

good post gaz

[tony TLC]

too much info for me thx
and hi all

[enduro]

I dont give a fxxx what its made of, all i want to do is lay it for as much money as i can get..

[Unregistered]

Granite - true granite is actually porous!! Most of the worktops you see used are not granites.

Not all limestones are porous!

"All natural stone should be sealed to prevent staining,it is a misconception that a polished stone tile is sealed....wrong,the polishing process exposes microscopic holes in the surface that will fill with dirt given time,this is irriversable.All natural stone manufacturers will have a reccomended sealant."

The above quote is scandously wrong - it is generally wrong to seal a polished stone as the surface is so smooth it holds back liquids. The polishing process does not expose holes, it actually closes holes. Surface damage caused by acidic spills and foot traffic may fill with dirt, but this can be sorted out by a stone restoration professional who will hone and repolish the stone.

[Dan]

Thanks for your added info Mr Unregistered.
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I've stuck the topic as it's a good one.

[McP77]

Mr Unregistered.

I think you've brought up a good point here that each stone has to be treated individually. You're right that granite is porous and not all limestone is very porous. Following on from that though I'd say that some polished stones benefit from being sealed, some don't. No blanket policy.

As for polishing exposing/closing holes - I know that the polishing process exposes holes on a polished porcelain. When you say that it actually closes holes is this on things such as polished marble and other such natural stones?

(Every day's a school day!!)