Frequently asked questions

RMC material is made of natural marble, which is extracted from regional quarries. As one of the first production phases is crushing and mixing of stone, RMC doesn’t have specific requirements for the shape of the blocks, and therefore the leftovers from the quarries can be used. RMC also focuses on sustainability during the manufacturing process. All water used for cutting and surface polishing is recycled in our water treatment plant, which saves hectoliters of water every day. One of our internal projects successfully reached the stage where we can reuse selected construction material from demolition, such as bricks, concrete or glass.
More information is available on the sustainability page.

Generally, yes, although it requires special care similar to other natural surfaces such as marble or wood. As RMC material contains approximately 95% of natural marble, it is sensitive to contact with acids (e.g. lemon juice), especially in a combination with strong pigments (e.g. red wine). These can damage surface of RMC material (usually loss of gloss, corrosion or a stain). RMC offers the application of antiacid impregnation for honed surface as a partial protection against accidental contact with acid. Nevertheless, the surface has to be cleaned swiftly and still very aggressive liquids may create a light stain. Regular maintenance with the right cleaning agent (pH neutral) is also a key factor.

RMC material is one of the best options for facades, windowsills and other outdoor applications thanks to its low water absorption and shade consistency. We are always amazed by the great look of RMC tiles installed 30 years ago on the facades of Portuguese houses near the ocean, facing harsh weather conditions including salt, humidity and extreme temperatures. Obviously, every material has its limitations when used outdoors. In the case of RMC, there are two aspects worth mentioning: color fading ang loss of gloss.

As with natural marble, the darker colors of RMC tend to fade and take on a lighter/greyish tone over time. This effect is caused by UV radiation and is common to all natural stone-based materials (RMC, terrazzo, quartz). There are chemicals available on the market that significantly slow down this process. RMC supplies a Color Enhancer for exteriors that makes colors more vibrant and provides UV protection.We continually test our material by exposing it to different weather conditions and our tests show that dark colors such as Merrazzo Black, Madeira or Dark Grey start to fade noticeably after about a year. When using a color enhancer, it is difficult to see any significant difference in our tests.

The second topic is the effect of weather conditions on the surface of the material, where the only limitation is the polished finish. Over time, marble tends to lose its gloss and naturally changes from polished to honed or matt. This is why we do not recommend a polished finish for facades and exterior applications in general.