The Engagement Ring Buying Guide

This is the long version. If you want the order of decisions without the detail, read how to choose an engagement ring first.

The 4Cs, briefly and honestly

The 4Cs are the grading language for diamonds, developed and popularized by the Gemological Institute of America (GIA).

Cut. How well the stone’s proportions and polish return light. GIA assigns a cut grade (Excellent to Poor) to standard round brilliants; for other shapes, you judge proportions and appearance from the report details and images.

Color. For white diamonds, a scale from D (colorless) to Z (light yellow or brown). Differences of a grade or two are hard to see once the stone is set, especially in yellow or rose gold.

Clarity. From Flawless to Included, based on inclusions and blemishes under 10x magnification. Many stones in the middle grades look clean to the eye; the location and type of inclusion matters more than the grade alone.

Carat. Weight, where one carat is 0.2 grams. Two stones of the same weight can look different sizes depending on how they are cut.

Reports and disclosure

A grading report from an independent laboratory describes the stone. It is not an appraisal and does not state a value. Check that the report number matches any laser inscription on the stone.

In the United States, the FTC’s Jewelry Guides set expectations for honest description. Lab-grown diamonds should carry a clear qualifier such as “laboratory-grown”, and treatments that significantly affect a gem’s value or care, such as fracture filling or oiling, should be disclosed. If a seller cannot tell you whether a stone is treated, treat that as an answer.

Settings and security

Prongs are the most common setting and show off the most stone. Six prongs hold more securely than four. Bezels protect the edge fully and suit active lifestyles. Halos add perceived size, and pavé bands add sparkle, but both add small stones that need periodic checks. See halo engagement rings and solitaire engagement rings for more.

Metals

Platinum and gold are both excellent choices; the differences are about color, weight and upkeep rather than quality. Our metals guide covers karats, rhodium plating and allergies.

Policies that matter after you pay

Before paying, find and read:

• Returns. Window length, condition requirements, and whether custom or engraved pieces are excluded.
• Resizing. Whether the first resize is free, and whether the design can be resized at all.
• Warranty. What it covers. Most cover manufacturing defects, not accidental damage, loss or theft.
• Upgrades. Some jewelers credit the original stone’s price toward a larger one later; the terms vary widely.

Questions to ask any jeweler

1. Can I see video of this exact stone in natural and indoor light?
2. Is there an independent report, and does it match the stone?
3. Has the stone been treated in any way?
4. What is the production time, and what happens if it runs late?
5. Which parts of your return policy apply to this ring?

Once you have the answers, you are comparing like with like.