At present, the price difference of slate with similar specifications sold online can reach 30% to 50%, which is caused by the differences in raw material quality, processing technology and purchase channels, among which the most important influence is the material and technology. Consumers should pay attention to the following aspects:
1. Choose slate with high cordierite content.
Cordierite, as the main material, has a great influence on the fire resistance of slate. If poor quality cordierite is used, the cost will be reduced, and the fire resistance of the household oven is 200-300 degrees, but it is still enough to fish in troubled waters. But the consumer can't see it with the naked eye, and he doesn't know if you ask the customer service. But don't worry, in order to further reduce the cost, some manufacturers will not only reduce the cordierite content.
Raw material cordierite
2, slate should be fully sintered, flat particles in solid powder.
As long as there is enough firing time and proper firing temperature (generally 1200℃), the slate can be completely sintered, harder and more fire-resistant. Otherwise, the powder on the surface of the unsintered slate will fall off and the particles on the surface will look unstable.
Unsintered slate surface
Shortening firing time and lowering firing temperature can reduce fuel consumption and cost, but the unsintered slate will fall off, not only because of the accumulation of foreign dust on the surface, but also because the material itself falls off, which can be easily seen even without looking at the real thing.
All-sintered slate surface
3, the appearance should be smooth and detailed without big black spots.
All kinds of raw materials should be treated before mixing, and some manufacturers will omit some working procedures. For example, a step that has a great influence on the appearance of finished products is to remove iron impurities with relatively large particles in raw materials, otherwise dense iron particles will appear on the surface of products after firing.
The surface of the stone slab without iron removal is densely covered with black spots.
There are not many black spots on the clean slate surface.
Polishing slate after firing is a time-consuming and labor-intensive process. You can save some cost if you don't grind it.
Unpolished slate edge
General quality and workmanship are positively related to the price, but of course, it does not rule out that some businesses' complicated purchase channels have raised the price. Slate is just a brick for burning things, not jade porcelain. It doesn't need to be perfect and meticulous, but it doesn't need experts to distinguish it with a magnifying glass. The second and third points mentioned above can be seen as long as you are careful.