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Marble finishing technology

Artificial painting of marble

As you know, all the colored varieties of marble are very expensive. Because of this, in the last time, artificial dyeing of more accessible white marble is widespread. The method of staining is as follows:

Unpolished marble is laid horizontally and covered with a dye solution (see below), so hot that it still foam. The coloring matter at that time creeps into the marble deeply also holds quite firmly. The dye solution is prepared in alcohol. For coloring in blue paint, litmus is dissolved in alcohol, the latter being determined by the desired density of color. For yellow color, a solution of gummigut is used. And if you put a second (gummogut) on top of the first color (litmus), then you get an excellent green color.

So prepared root solution alkanes, cochineals and so on. Stains marble in red. Finally, a solution in the alcohol of equal parts of zinc vitriol, ammonia, as well as copper-colored copper, stains the marble in golden color. You can make a very effective mosaic of pieces of marble of different colors, painted in this way: in terms of beauty and strength of color, it does not inferior to the mosaic of expensive varieties of marble, although it also costs much less.

Not every paint is suitable for painting marble or alabaster. To paint has also firmly held, it must be prepared as follows: make a solution of borax and vegetable coloring material, only then add to this solution a few drops of nitric acid or some nitric acid salt. For example, to paint marble in blue, a borax solution is prepared from indigo, and a few drops of nitrogen-iron salt (in the form of liquid) are also added. For painting in scarlet paint, dissolve any red vegetable dye with borax. Replacing the coloring matter with ink nuts, they also obtain for the marble alabaster solid black paint.

It is known that gypsum, mixed with water and then hardened, does not differ in strength: it becomes extremely fragile, and therefore acquires relatively little use. In order to eliminate this flaw, the plaster is also more firm, the following is used in America: 6 elements of gypsum are mixed with 1 part of slaked lime, and this mixture is then manipulated, as if with ordinary gypsum.

Items made from such a mixture, after a good drying, are impregnated with a solution of zinc sulfate. Items made of gypsum, processed in this way, are much stronger than ordinary gypsum handicrafts.

Prepare a thick solution of gum arabic, also using a brush cover them with marble, only then allow the gum arabic to dry completely. When the latter dries, it is separated from the surface of the marble (dried gum arabic easily lags behind the marble), and together with gum arabic, all extraneous substances contaminating the marble, which are difficult to remove by simple washing of marble, are also removed.

Another way: prepare a mix of 1 part by weight of chalk, the same number of finely divided pumice also 2 elements of soda. From this mixture makes the preparations on water a dough-like mass, which covers the contaminated parts of marble, then washed with water and soap. For the removal of greasy spots the latter are covered with chalk: the chalk is poured in a powder form on the marble with a sufficiently thick layer, after which the chalk layer is well wetted with gasoline only to eliminate rapid volatilization. The final chalk washed with gasoline is covered with a saucer turned upside down. After a few hours, the chalk is removed and also, if the fat stain still remains, again the same operation is repeated with fresh chalk as a new portion of gasoline. Another time the marble is covered with rusty metal stains. To remove them come as follows: in ammonium sulphide, good quality clay is disintegrated until a pulpy mass is obtained. Mass this is applied a thick enough layer on the stain. After 10-15 minutes, remove the mass and apply a fresh portion, which after 5 minutes is also removed, after which the marble is washed with water and dried. If the stain still remains, then at the time proceed to the secondary finish: the speck is covered with a dough-like mass, prepared from 1 weight element of a white bolus, also 4 parts of a solution of the potassium syneride (a poison that requires careful handling). This mass is left on the marble for 30 minutes, after which it is removed and the same operation is repeated; Then the marble is washed and also dried. Thus, it is possible to remove from the marble surface even the most ancient metallic rusty spots