The term 'FLAT SURFACE OF GEM' can be summarized as a TABLE, which is a flat surface of a gem. A TABLE is the flat, polished top surface of a cut and faceted gemstone, which is usually round or oval in shape. It is the largest facet on a gemstone, and it is the most important facet in terms of the gem's overall appearance. The TABLE is the first thing that people notice when looking at a gemstone, and it is the most important factor in determining the gem's value.