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Marble finishing technology

Artificial painting of marble

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

The unpolished marble is laid horizontally and covered with a dye solution (see below), so hot that it still foam. The colorant at that time creeps into the marble deeply also holds very 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 the 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 alcohol of equal parts of zinc vitriol, ammonia, as well as copper-colored copper, stains marble in golden color. You can make a very effective mosaic of pieces of marble of different colors, painted in this way: the beauty and strength of color, it does not inferior to the mosaic of expensive varieties of marble, although it also costs much less.

Paint for marble is also alabaster

Not every paint is suitable for painting marble or alabaster. To paint has also firmly held, it must be prepared in the following way: 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 solution of borax from indigo is also added a few drops of the nitrogen-iron salt (in the form of a liquid). For painting in scarlet paint, dissolve any red vegetable dye with borax. Replacing the coloring matter with ink nuts, also obtain for the marble alabaster solid black paint.

Post hardness of gypsum

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 from gypsum, processed in this way, are much stronger than ordinary gypsum handicrafts.

Cleaning marble

Prepare a thick solution of gum arabic and also brush them with marble, 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 the simple washing of marble, are also removed.

Another way: prepare a mix of 1 part by weight chalk, the same number of finely divided pumice also 2 elements of soda. From this mixture makes a preparation on the 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 thick enough layer, after which the chalk layer is well wetted with gasoline only to eliminate the rapid volatilization of the final chalk smeared with chalk covered by a top-topped bottom saucer. After several hours, the chalk is removed and also, if the fat stain still remains, again the same operation with fresh chalk is also repeated with 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 mushy 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 of the white bolus, and 4 parts of the 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