Ornamental stones selection

The selection of ornamental stones taking into consideration its characteristics
Besides the simple description of the stone surface, in which is taken into consideration the colour of the mineral elements and texture (relative dimension of grain and its structural position), elements that normally are checked through a deep petrografic study, it is important to do a series of physical-mechanic tests in order to find out the: 

- Compression strenght (simple);
- Bending strenght;
- Volumetric weight (apparent density or apparent volumetric weight);
- Water absorption (to pressure or normal temperature);
- Open porosity (or apparent porosity);
- Ice resistance; 
- Abrasion test;
- Impact test (minimum height)

Author: A. Casal Moura (Geólogo)
Source: Rochas & Equipamentos magazine