What is refractory high alumina brick looks like?

During purchase high alumina bricks,if you want to buy a high quality high alumina brick,you should consider the following factors:

First:the color, high-quality high-alumina brick brick body surface smooth, yellow color white, four equal, no broken angle, no cracks

The second, the weight of a single brick. According to the weight of 

high-alumina brick single 4.5 kg, two high-alumina brick for the 4.2 kg, three high-alumina brick for the 3.9 kg. The same level, the same type of high-alumina brick, if the weight of a single brick to achieve this standard, but for high-quality high-alumina brick, and vice versa to achieve such a weight, then that good quality. Such as the discovery of cracks, large split angle, four sides are not equal, it is for substandard products.