What is may the main impurity in Quartz Stone

As the Quartz Stone is one kind of man made stone, so there may be impurity. Then what may be the main impurity for the Quartz Stone and how could we avoid there will be impurity in Quartz Stone?

1.       the mostly content of quartz stone is quartz, which is natural material. Then there should be some impurity in the quartz. So need we to inspect the quartz material and deal with it carefully, otherwise, the impurity will be mixed into the quartz stone as the raw material mixing;

2.       during the material mixing, mostly depends on manual mixing, then there may be some different kinds of quartz or other kind of material which will stick on the gloves or on the tools. So need we to pay attention to clean the gloves or tools after finishing mixing of one kind of color to another kind of color. Otherwise, the different kinds of raw material stick on the gloves or tools will be into the Quartz Stone and becomes impurity.

3.       during equidistributing the mixed material on the mould, will use the wood to fix the material in the mould, avoiding it will come out. Then there will be bits of wood into the Quartz Stone accidently. So need we to pay attention when do equidistribution. Otherwise, there will be bits of wood into the mixed material and become impurity.