BijanDiamonds.com Dictionary
Rose Cut:
THe Rose Cut was developed in the 16th century. It has a flat bottom and domed top covered with triangular facets. The outline varies, but rose cuts are most typically round, oval, triangular or pear-shaped. In the 17th century, they gained greater acceptance and their facet arrangement became less random. Variations were always in multiples of six, such as a six-facet rose, an 18-facet rose and the full rose cut, which has a lower tier of 18 facets and upper tier of six facets coming to a point at the apex, which makes it look like a rosebud just starting to open.