Common faceted shapes include round (maximum brilliance), oval (elongated elegance with good color display), cushion (soft corners, vintage appeal), emerald (step-cut rectangle highlighting color), pear and marquise (tapered outlines for finger-lengthening illusion), and princess (square brilliant). Each shape affects weight retention from rough, perceived color intensity, and brilliance.
Cabochon shapes (domed top, flat base) suit translucent or opaque gems to display phenomena like chatoyancy (cat's-eye) or asterism. Shape selection balances optical performance, durability (avoiding pointed corners on cleavage-prone stones), and market demand. Well-proportioned stones with good symmetry command higher prices than shallow or deep cuts that leak light.