Rock Dandruff

What is rock dandruff? 

The deposition of salt and mineral salts resulting from the evaporation of mortar water behind the stone and the composition of the stone itself causes dandruff and whitewash on its surface. Stone scale is completely natural because the nature of the stone is natural and contains compounds such as sodium and calcium sulfate, on the other hand, the type of mortar used behind it is also very important.

  The cause of rock dandruff 

Scaling of stone is more common in humid environments because salt and mineral salts are more easily transferred to the surface of the stone through moisture. On the other hand, the lower the density of the rocks, the more the way of transferring salt solutions to the surface of the rock and its evaporation. Therefore, resin and epoxy are used to make travertine stones, which have relatively high porosity, impermeable.  So, in general, the cause of stone scaling can be summarized in the following cases:  • The presence of mineral salts and soluble salts in mortar and stone compounds  • Ambient humidity  • Low density of rock    

Are there dandruff and whites in all the stones? 

According to the above three points, it can be seen that the possibility or impossibility of whitewash is highly dependent on the following factors:     The type of stone, brick and any material and the presence of salt in its elements. Some of these elements are “calcium sulfate” and “barium carbonate”.  density of stone or brick; The denser the rock is and the fewer pores it has, the less the possibility and rate of salt formation. In this way, it can be said that stones like travertine are more prone to whitewash.  More humidity leads to more whiteheads and dandruff. For this reason, usually in humid areas (such as the north of the country), more scales are seen on stone and brick facades.  Of course, in addition to the stones and bricks themselves, the presence of salts in the mortar is also the cause of dandruff. The higher the moisture content in the mortar, the more this phenomenon will be seen.

  Prevention and removal of dandruff 

There are several methods to prevent and fix limescale, which we briefly mention.  Use of washed sand or sand with less salt and sulfate compounds  Using a mechanical and dry method where the stone is installed on the facade by screws, plates and pins  In addition to the relative impermeability of the stone, resin and epoxy make the stone shinier and more beautiful. Be careful that resin and epoxy do not make the stone 100% impenetrable.  Grinding the surface of the stone with a rough cloth or sandpaper (not recommended because it will cause scratches).  Washing with water and brush, which is a temporary method, you may face this problem again after the water dries.  The use of nano products that have hydrophobic properties and greatly reduce water absorption. Therefore, these products can be used as an anti-dandruff solution.  The use of salt ink is the best and most effective way to remove dandruff. For this purpose, dilute the essence of salt with water and pour it on the surface of the stone. It should be noted that for the durability of this solution, water-repellent materials must also be used. 

Removing dandruff and white stone 

Even though the cause of dandruff on brick facade is similar to stone, however, different methods are used to remove this dandruff in each of them. Here we are going to briefly explain the methods of removing dandruff and white stone.   

  Grinding and cleaning the whites 

In the initial stages of the formation of this dandruff, their hardness is very low. In this way, you can remove them easily with only fabrics with almost coarse textures. Of course, sometimes the use of high-pressure water is also recommended for this. 

Use a brush 

Another available solution is to use a brush with water pressure to remove this dandruff. Of course, when using this method, you must pay enough attention to the texture of the stone and do not damage it. Since the main cause of dandruff is moisture, it is possible that the water you use to clean it is itself the cause of subsequent dandruff.   

  Use of detergents 

Some people use strong detergents such as salt ink to remove salts and remove them from the surface of the stone. It is recommended not to use such materials on the stone. Because most of the stones lose their appearance in contact with these detergents. 

Use of nano materials 

If you are familiar with nano products, you must know about their water repellency. The use of such materials on the stone greatly reduces the absorption of water in it. The lack of water absorption reduces the formation of soluble salt and, as a result, whites do not form on the surface of the stone. Therefore, these products can be used as anti-dandruff materials.