With the accelerated pace of reform and opening up and the continuous improvement of people's living standards, the application of natural stone has become more and more extensive and popular. It has developed from public buildings to thousands of households, and its value and function have changed from simple building materials to high-end decorative materials.

From a geological point of view, there are a wide variety of natural stone materials currently on the market.

However, from a commercial point of view, we summarize the natural stone we are exposed to as followsSeveral types of marble, granite, slate and sandstone.

Among them, granite comes from volcanic eruption, so its particles, crystalline state, color and so on are relatively uniform, but also relatively hard, with high compressive and bending strength, often used in outdoor decoration;

Because marble comes from sedimentary rocks and metamorphic rocks, it has the characteristics of high density and pure color.

With different colors of stripes and patterns, the marble is elegant and beautiful. It is often used in the lobby and elevator of high-end buildings and star hotels. The strength of marble is lower than that of granite, so it is often used in interior decoration.

Although the application of stone has been more popular, people are not unfamiliar with it, but from the perspective of the entire industry, the research on stone is not very in-depth, and some of its properties are not well understood.

Especially in the stone application design also mainly rely on empirical methods. All of these have brought some inconvenience to the optimal use of stone. In general, in the choice of stone should pay attention to the following aspects:

The use of stone occasions

The application of stone is divided into external use and internal use. For external decorative stone, due to its harsh environment, there are the influence of weather, the influence of harmful substances, the influence of wind load and so on.

Granite products with high strength are selected; as interior decoration materials, the main pursuit of beauty and creativity, the pursuit of gorgeous, simple effect. Of course, for the indoor lobby, stair steps and other parts, also can choose small color difference, good granite.

The quality of the product

Stone quality mainly refers to the physical and mechanical properties of stone, including water absorption, bulk density, dry compression strength, bending strength. In general, the volume density of stone is small, and the water absorption rate is relatively high.

This kind of stone, from the appearance of the material is relatively loose, its essential defect is that the porosity of the material is large, easy to inhale various impurities and dirt in use, resulting in premature failure of the stone; the compressive strength and bending strength of the stone are low, not only can not meet the design and use requirements, but also is a serious engineering hidden danger.

Therefore, after selecting a certain stone, it is better to have a qualified quality inspection department to do physical performance testing, which is particularly important for dry hanging stone on exterior walls.

According to the different occasions of use, the evaluation index of stone quality also includes:Wear resistance, frost resistance (change in compressive strength after freeze-thaw cycles), hardness, shear strength, chemical composition contentWait. When the stone as the ground decoration material, should also pay attention to itsHardnessandWear resistance index.

Appearance quality of the product

The front feeling of stone products to people is its external beauty. Consumers can choose a certain kind of stone products (such as red, yellow, etc.) according to their personal aesthetic point of view and use occasions and the nature and use of buildings, and then determine the variety of stone (such as cherry blossom red, Anxi red, etc. in red varieties).

When selecting stone, check whether there are any on each side.Defects such as cracks, missing edges, missing corners, color spots and color lines exist..

In order to ensure a good decorative effect, consumers can place a batch of stones flat on the site irradiated by natural light before purchase, and visually check whether the color tone of the product is consistent at a distance of about 1.5 meters from the stone.

product processing quality

Processing quality

Size, flatness, angle, mirror to gloss is an important aspect of reflecting the quality of processing, but also an important basis for the grading of natural stone.

The use of different grades of stone, after the installation of the effect will be different. The higher the grade, the better the effect, but the higher the price.

Consumers should choose the grade they need according to their actual situation, pay attention to the actual engineering, do not blindly pursue high grade, in order to reduce unnecessary costs.

At present, the stone standards are GB/T18601-2001 and JC/79-2001, which correspond to natural granite and natural marble products respectively. Users can inquire according to their needs.

purchase and sale contract

Purchase and sale contract

Before purchasing stone products, consumers must sign product purchase and sales contracts with suppliers or ask for invoices, clarify the product name, specifications, grade, quantity, price and other subject content and quality assurance terms, and clarify which standard to use for testing.

If necessary, the inspection institution and the dispute arbitration organ may also be agreed in advance. When purchasing stone, it is better to ask the supplier to provide an inspection report that can prove that the product is qualified.

radioactive problem

Radioactivity problem

In 2003, 16 varieties were selected as Class A, without Class B or Class C. The GB6566-2001 Radionuclide Limits for Building Materials, which came into effect on January 1, 2002.

The radioactive index of natural stone has been scientifically and reasonably relaxed. In this way, the use of unlimited stone types will reach more than 95%.

Stone surface protection

Stone surface protection

Due to the existence of acid rain, salt spray and harmful gases in the atmosphere and the existence of alkaline substances in cement in wet construction, the stone will have different degrees of corrosion and damage.

For road stones, long-term foot and dirt erosion will also affect the life and appearance of the stone. Therefore, in recent years, more and more projects have adopted stone protection technology to prevent premature aging and pollution of stone.

Stone protective agent can prevent stone corrosion, anti alkali, pollution, weathering and so on. At present, there are many kinds of protective agents on the market, including domestic and imported ones, and the protective effect is uneven. Here to remind consumers in the selection of protective agents must be careful.

Prevent fake and inferior products

Prevent fake and shoddy products

Under normal circumstances, consumers can buy their own satisfactory stone, but after years of work and practice, we have found that some illegal merchants have adopted some improper means in their business activities, bringing losses to users and even disputes. The methods of illegal merchants are roughly the following:

1, shoddy, that is, when the contract is signed with the customer high-grade products, but when the supply is mixed, even when the customer is not paying attention to, not present to mix the defective products.

2, with ordinary varieties pretending to be famous varieties, with domestic varieties pretending to be imported varieties.

3. Copy the inspection report, transfer flowers and trees, and apply the inspection conclusions of others to their own stone products.

4, exaggerated, exaggerated propaganda, with "international A- level", "super" and other non-existent standard levels to deceive users.