The difference is that there is actually a difference in quality between imported diatomaceous earth and domestic diatomaceous earth, but you haven't figured out the goals of the two. Diatomaceous earth is a natural mineral resource and has a wide range of uses. One of the primary physical and chemical goals of diatomaceous earth is amorphous silica, and the higher its content, the purer the diatomaceous earth, which is commonly referred to as "quality". However, the primary focus of diatomaceous earth used in diatomaceous mud is on specific surface area and pore volume targets, which are not supplied by domestic diatomaceous earth manufacturers, while imported diatomaceous earth is a necessary target. The color of domestic diatomaceous earth is relatively dark, and it is basically purified by calcination. The pore size of the original diatomaceous earth ore is burned down at a temperature of 800 degrees Celsius. Although the whiteness is increased, the specific surface area and pore volume are greatly reduced, even to 1-2 square meters. The respiratory function becomes very weak. The color of diatomaceous earth from abroad is relatively white, but the purification skills still need to be advanced, and the specific surface area can be retained at more than 20 square meters. Of course, not all imported varieties of diatomaceous earth have such a large specific surface area, and manufacturers need to conduct their own testing. Good quality of diatomaceous earth can ensure the respiration and humidity regulation of diatomaceous mud. Good domestic manufacturers of diatomaceous mud usually choose marine diatomaceous earth.