Afacet is a on a gem. polished surface cleavage plane small impurity crystal face

Option (1)

Explanation:

A Facet is usually defined as a flat surface that represents the polished surface on a gemstone that is being cut in a preferred geometric manner on the surface of the well transparent surfaces of a gem. It is comprised of three or four prominent sides. This process of cutting, polishing and making facets is commonly known as faceting.

The widest part within a faceted stone is referred to as girdle and it is located directly on a plane in such a way that it differentiates the crown.

Thus, the correct answer is option (1).