144 BULLETIN 118, UNITED STATES NATIONAL MUSEUM. 



PORTUGUESE CUT. 



The figures show the top, side, and bottom views of the Portuguese 

 cut, which has two rows of rhomboidal and three rows of triangular 

 facets above and below'the girdle. 



b c 



Fig. 20.— The Portuguese cut. top (a), side (6), and back (e) views. 

 STAR CUT. 



The figures show the front and back views of the star cut. The 

 table is hexagonal in shape, and is one-fourth of the diameter of the 



a b 



Fig. 21.— The star cut, front (a), and back (6) views. 



stone; from the table spring six equilateral triangles, whose apices 

 touch the girdle, and these triangles, by the prolongation of their 

 points, form a star. 



ROSE CUT. 



The rose cut differs from the brilliant cut in that the crown con- 

 sists of triangular or star facets, whose apices meet at the point or 



a b c 



Fig. 22.— The rose cut (a) and (6), top and side views; (c) side view of double rose. 



crown of the rose. The base lines of these star facets form the base 

 lines for a row of skill facets whose apices touch the girdle, leaving 



