Cut decides how much light a diamond returns, so start there. Then choose color and clarity that are invisible to the eye, and carat for the presence you want. The 4Cs · Diamond Clarity

Round for the most brilliance, oval and pear to lengthen the finger, emerald for depth and clarity, cushion for broad flashes of light. Diamond Shapes

Size the ring finger at the end of the day, and make sure the ring will pass over the knuckle. If you are buying in secret, measure a ring they already wear on that finger. If you need a different size, tell us before your order ships; after delivery, an unworn ring can be exchanged for another size within 14 days. Eternity rings cannot be resized. Size Guide

Prongs show the most of the stone and let in the most light; a bezel protects its edge. A solitaire puts everything on the center stone; a halo or pavé band adds light around it. Choose the metal to suit the wearer: 14K is the most practical for daily wear.

A wedding band should sit flush beside the engagement ring. Choose them together, in the same metal and karat, so they wear evenly. Wedding and eternity bands

If your ring includes an IGI grading report, the product page says so and the report travels with the ring. Keep it with your order confirmation; you will need both to insure the ring. Diamond Documentation

Every ring carries our 3-month limited warranty. For loss, theft and accidental damage, insure it with an independent jewelry insurer. Jewelry Care