In most african artworks including sculptures and masks artists make the entire surface shiny and sore smooth with what do africans associate this type of surface

Cultivated refinement  

Explanation:

Most African artworks are done in this manner because the shiny and smooth surface of the finished works is considered a sign of refinement. There are two particularly important reasons for this. The first one is that, when depicting people, this surface is associated with beauty, shine and health. The second one is that such a polished finish is considered a mark of fine workmanship and mastery of the medium. Therefore, it is evidence of the sculptor's talent.