
왜 일부는 자연석 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.

석회암, 사암, 셰일은 퇴적암의 가장 일반적인 유형입니다. 이는 수백만 년에 걸쳐 해저에 떨어진 퇴적물을 지탱하는 엄청난 압력을 통해 형성되었습니다.
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.
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.
사암은 아마도 1800년 이전에 교량부터 웅장한 건물에 이르기까지 모든 건축용 석재로 가장 일반적으로 사용된 석재였습니다. 이름에서 유추할 수 있듯이 모래, 유기물, 방해석 및 기타 다양한 광물이 수천 년에 걸쳐 엄청난 압력을 받아 함께 융합될 때 형성됩니다. 거칠거나 미세한 질감으로 제공되며 전통적으로 무광택 마감 처리로 제공됩니다. 영국에서는 주로 크림색, 빨간색 또는 회색이며, 그 색상은 포함된 추가 미네랄에 따라 달라집니다. 실리카는 흰색을 띠고, 철은 적갈색을 띠게 됩니다. 주요 적용 분야는 벽과 바닥 또는 외부 포장입니다.
대리석은 수백만 년에 걸쳐 엄청난 열과 압력의 변태를 통해 형성된 석회암의 파생물입니다. 다른 돌에 비해 상대적으로 부드럽지만 대리석은 놀라울 정도로 잘 연마되는 경향이 있습니다. 전통적으로 대리석은 문에 사용되며 고급 마감재를 만드는 데 도움이 됩니다.