Simple Method for Quality Evaluation of Granite Stone

Identification of color lines and stains

 The color lines and stains in granite stone are formed during the formation of rock or in the later stage due to the local enrichment of some minerals or being wrapped by other minerals. Strip or tuberculosis, the main mineral composition is quartz and dark-colored minerals such as biotite and amphibole; quartz forms quartz veins in the rock, mainly in the form of white strips in the stone, biotite, hornblende The dark minerals in the stone are formed into strips or tubercules by different formations.

 Color lines and stains can be used by people in addition to some special patterns in rare cases. In stone, they are defects due to their different colors from stone. If you use colored lines and colors in decoration, The spotted stone will seriously affect the decorative effect. At the same time, because the mineral composition of the color line and the color spot is different from the main mineral composition of the stone, the stress concentration area will be formed on both sides or around the color line and the color spot. The stone is in these places. It is prone to cracks or breakage. The color lines and stains formed by the dark mineral black mica are not convex or concave due to the special sheet-like structure during the stone grinding and polishing process.

Grading of granite stone

 The blocks of granite stone are taken from different locations in the rock mass. The rocks in different positions of the rock are different in the role of the various materials they are subjected to, and the effects of the rocks after diagenesis are also different.

Taking weathering as an example, the rock in the edge region or surface of the rock mass is subjected to the strongest weathering, so that the weathering phenomenon of the rock is serious, and the structure becomes loose. Such stone grinding and polishing is difficult, and the processed stone color is difficult. It is not bright, and its flexural strength and compressive strength are low. The rock weathering in the rock body or in the center is weak, and the rock minerals have almost no change. The rock is fresh, the structure is dense, and the color is bright.

Evaluation of Grinding and Polishing Quality

 The gloss of the facing stone is an important criterion for evaluating the quality of the stone. The size of the gloss depends, on the one hand, on the refractive index of the various minerals that make up the rock and on the other hand is closely related to the microstructure of the stone surface.

 The same granite stone has a certain mineral composition. The smoother the surface, the less the concave and convex defects, the higher the gloss of the stone. The microstructure of the stone surface is determined by the quality of the grinding and polishing process.

 Due to the wide variety of granite stones, the genesis and mineral composition of various stone materials are different. It is difficult to put the quality evaluation criteria for granite stone. However, by analyzing the quality of stone grinding and polishing and the problems that often appear on the market, the methods of evaluation and identification are very important for guiding people how to purchase granite stone.