How to polish dull marble by hand using MARBLE RESTORE kit
Using the MARBLE RESTORE kit you can get a perfect polishing of “marbles” with high carbonate content. For marbles with spurious carbonate content, on the other hand, you will achieve a polishing with less gloss. In such cases, in order to obtain the same degree of gloss, it will be necessary to complete the work with a specific wax .
Keep in mind that the “gloss” is the unit of measurement for the brilliance of a material. It varies between 0 and 100% of reflected light and can be measured with a reflectometer or a gloss meter.
How to polish marble by hand
In the MARBLE RESTORE kit you will find three velcro backed diamond plates; they are three abrasive plates made of resin mixed with fine diamond powder. Compared with carborundum abrasive papers, they have the advantage that they never clog, and remain effective until worn out. These diamond plates present grits ranging from 400 to 1500.
Grit is usually identified by a number which in turn is associated with a certain color. The coarser grit included in the kit is the number 200, with a red velcro back. 200 grit is not the coarsest available on the market for this type of abrasive resinoids (grits 60 and 100 are also produced). With a grit 200 plate you are able to eliminate surface roughness that is perceptible to the touch, and even small scratches, if you exercise enough pressure on the pad and if you carry on rubbing for long enough.
Avoid using too rough grits
However, to restore the polishing of a surface, it is not always necessary to start the job with the coarsest grit. On the contrary, it is recommendable to start working with grits as fine as possible in relation to the roughness of the surface to be polished. In principle, you should start with a grit 200 if the roughness of the surface is clearly perceptible to the touch. If, on the other hand, there is a mark that is only visible when looking closely against the light, but is imperceptible to the touch, you can consider sanding with grit 1500, which is the finest of the series and the last one to be used before chemical polishing.
Which abrasive to use?
This following photos will help you decide which grit you should start the sanding work with.
Above slight corrosion imperceptible to the touch (etch mark)
The etch mark above can be eliminated using 400/800 grit abrasive
Heavy corrosions : start using grit 200
After passing the diamond abrasives on the surface, the final phase of the recovery work involves the use of a special polishing powder. This phase aims to replicate the so-called “varnish” process, but is carried out without using lead, machines, oxalic acid, or other toxic substances. In our case, the polishing is obtained simply by hand rubbing a paste made of polishing powder and water with the help of a cloth on the surface previously sanded with diamond abrasives. The secret for a perfect recovery work is a good sanding work, done with the utmost care. You will need to completely erase the signs of the previous grit at each step. The powder contained in the kit is a mixture of resins and metal oxides which, rubbed on the marble, causes the chemical polishing by filling all the micrometer sized pores with calcium molecules. It is not a glazing powder and does not cause the formation of any glass-like film on the marble surface.