Sandblasting is the process of using an aluminium compound in a machine similar to a vacuum, but instead of vacuuming, the machine blows the particles onto the surface to roughen it and make it appear matte. Sandblasting does not have a colour, instead it just appears to be the colour of the original object but in a matte form. Eg. Clear window glass will appear a whitish, but opaque colour. Dark granite will still appear as granite but the roughened surface will be more prominent and may appear slightly lighter than the smoother surface.