Lab-Grown Diamond Solitaire Necklaces

Round leads this group and throws back the most sparkle for its face size. Princess and emerald cuts bring squared corners and a cleaner, architectural feel. Pear, oval and marquise outlines point downward and lengthen the neckline. A heart shape feels personal, the classic gift stone.

• Open prong head: admits light from every side, the classic way to hang one stone.
• Basket: prongs tied together by a metal ring for a steadier seat.
• Bezel rim: a smooth collar on some designs, the most protective option.

Most designs offer 1 to 9 carats, so the stone can be scaled to budget and neckline. Gold comes in 10K or 14K, white, yellow or rose. Silvadium, a sterling silver alloy that won't tarnish easily, lowers the price for the same stone. A colorless stone looks brightest against white gold or silver.

With a solitaire, a film of lotion on the pavilion is what dulls it most. Soak the pendant in warm water with mild soap, brush behind the stone and rinse. Every few months, look at the prong tips for any movement.