DÈ NA CARRAIGHEAN NÀDARRA A THA A' BHOGHAIL AGUS Càit an tèid an cleachdadh? clach cruth-tìre

Carson a tha cuid clachan nàdarra considered to be soft when they all appear to be hard? The answer lies within ‘relative’ hardness. Mohs scale of hardness was invented in 1812 and compares the relative hardness of ten minerals. Diamond is the hardest and rates a 10, while granite is the toughest natural stone at 6. Limestone comes in at 3 as does its metamorphic counterpart, marble. Softer stone is easier to dress or carve but does not wear or weather quite as well as harder stone. Here we discuss some of the more popular soft stones along with suitable applications.

Clachan neo-riaghailteach

Creag ghrùideach

Is e clach-aoil, clach-ghainmhich agus clach-ghuail na seòrsaichean creige ghrùideach as cumanta. Chaidh iad sin a chruthachadh tro chuideam uabhasach, thairis air milleanan de bhliadhnaichean, a’ toirt sìos air grùid a bha air tuiteam gu grunnd a’ chuain.

Sglèat

The layers in slate are described as being “foliated” and they are easily split apart to create whatever thickness is required. UK slate is considered to be hard and was traditionally used as roofing, while soft slate is found in China, Spain, Italy and the USA. With a broad range of natural slate colours, a multiple array of designs can be achieved, from contemporary to classic, rustic to refined. Slate is often recommended for high traffic areas, thanks to its remarkably durable composition. It is also non-porous and does not easily react with acid liquids. It is fire proof, weather resistant and achieves good slip resistance dues to its riven finish.

clach-aoil

Limestone is a very common building material and is formed mainly from the mineral calcite, derived from the calcium in bones and seashells deposited over the millennia and forced together through pressure. While it also contains magnesium, it is harder and more weather resistant, and can also be polished. Portland stone from the eponymous island in Dorset is probably the single most famous type of limestone and was used to build many of London’s great buildings. It is used for external cladding as well as paving, fireplaces and other internal and external decorative features. Its soft colours are its trademark visual attributes.

Clach-ghainmhich

Is dòcha gur e clach-ghainmhich a’ chlach-togail a b’ àbhaist a chleachdadh ro 1800, airson a h-uile càil bho dhrochaidean gu togalaichean stàiteil. Mar a dh'fhaodar a dhearbhadh bhon ainm, tha e air a chruthachadh nuair a chaidh gainmheach, stuth organach, calcite agus measgachadh de mhèinnirean eile a chur còmhla fo chuideam iongantach thar nam mìle bliadhna. Ri fhaighinn le inneach garbh no grinn agus gu traidiseanta air a thoirt seachad ann an crìoch matt. Gu h-àraidh uachdar, dearg no liath san RA, tha a dath an urra ris na mèinnirean a bharrachd a tha na bhroinn. Bidh silica a 'toirt seachad geal, agus bheir iarann ​​​​dearg-dhonn-dhonn. Is e na prìomh raointean tagraidh aige ballachan agus làr, no cabhsairean a-muigh.

Marmor

Tha marmor mar thoradh air clach-aoil, air a chruthachadh tro metamorphosis teas mòr agus cuideam thar milleanan de bhliadhnaichean. Ged a tha e an ìre mhath bog an taca ri clachan eile, tha marmor buailteach a bhith a’ snasadh gu math. Gu traidiseanta bidh marmor air a chleachdadh ann an dorsan agus a’ cuideachadh le bhith a’ cruthachadh crìoch àrd.