A diamond is a crystal made of carbon atoms arranged in a tight, repeating structure. That structure makes it the hardest natural mineral used in jewelry, and it is also why diamonds have strong “sparkle” when they are cut well. Diamonds form deep underground under high pressure and heat, then reach the surface through volcanic activity.

There are also lab-grown diamonds, which are real diamonds made in a controlled environment. They have the same chemical makeup and crystal structure as mined diamonds, but their market value is usually lower than comparable natural diamonds.

What is a diamond worth?

A diamond’s value can vary from very affordable to extremely expensive. Two stones that look similar at a glance can be priced wildly differently once you factor in quality details.

The biggest value drivers

1) The 4Cs

• Carat (weight): Bigger is usually worth more, but value jumps at certain “milestone” sizes (0.50, 1.00, 1.50, 2.00).
• Cut (proportions and craftsmanship): This is the biggest driver of beauty. A well-cut diamond can look brighter and even “larger” than a poorly cut diamond of the same carat weight.
• Color (for white diamonds): Less color is usually more valuable (often graded D through Z).
• Clarity (internal inclusions and surface marks): Fewer and smaller imperfections generally means higher value.

2) Shape
Round brilliant tends to cost more per carat than many fancy shapes (oval, pear, cushion, emerald), even when all other grades are similar.

3) Certification
A report from a respected lab can add value because it reduces uncertainty. No report can mean you are guessing.

4) Natural vs lab-grown
Lab-grown diamonds can look identical, but they often sell for less than natural stones at the same 4C grades.

5) Treatments
Some diamonds have treatments (like fracture filling or certain color enhancements). Treatments can significantly affect value and should always be disclosed.

Retail price vs resale value

This surprises people: jewelry resale is often much lower than retail. Retail includes branding, overhead, and setting costs. If you are buying for value retention, focus on:

• Strong cut quality
• Desirable color and clarity ranges
• A reliable grading report
• Avoiding heavily treated stones

How to estimate value without getting fooled

If you want a realistic sense of what a diamond is worth, do this:

1. Get the grading report number (or get the stone graded if it has no report).
2. Compare apples to apples: same carat, cut grade, color, clarity, shape, and fluorescence.
3. Separate the setting from the stone: a ring’s price includes metal and labor.
4. Watch for “too good to be true”: a 1-carat diamond priced like a tiny stone usually has a catch (poor cut, heavy fluorescence, low color or clarity, treatments, or it is not a diamond).

How to tell if a diamond is real

There are lookalikes (especially moissanite and cubic zirconia) and there are also lab-grown diamonds, which are real diamonds but not mined. “Real” can mean different things depending on what you care about:

• Real diamond: natural or lab-grown, both are diamond
• Natural diamond: mined
• Diamond lookalike: not diamond at all

Quick checks you can do at home (not perfect)

1) The “sparkle” check
Diamonds typically show a mix of white flashes and colored flashes, but this is not reliable by itself. Moissanite can throw even more rainbow fire and can fool the eye.

2) The fog test
Breathe on the stone like a mirror. Diamonds tend to clear quickly. Some fakes also clear quickly, so do not rely on this alone.

3) A basic diamond tester
Thermal conductivity testers can catch many fakes, but some will read moissanite as “diamond” unless the tester is made to distinguish them.

Checks that are more reliable

1) Look for a grading report
Ask for a diamond grading report and confirm details match the stone. Many certified diamonds also have a tiny laser inscription on the girdle that matches the report number.

2) Examine under magnification
A jeweler’s loupe (10x) can reveal inclusions and features. Cubic zirconia often looks overly “clean” and can show different wear patterns over time.

3) Rule out moissanite
Moissanite can look extremely similar. Many jewelers use specialized testers or optical tools to separate moissanite from diamond quickly.

4) Identify lab-grown vs natural
A standard jeweler loupe cannot reliably confirm origin. Distinguishing lab-grown from natural often requires advanced instruments and screening used by jewelers and gem labs.

Common scams and red flags

• “Certified” with a vague in-house paper that is not a real lab report
• Unrealistic grades for the price
• No return policy or pressure to buy immediately
• Misleading language like “diamond simulant” without clearly saying it is not diamond
• Treated stones not disclosed

The safest way to buy a diamond

• Buy from a seller with a solid return policy
• Prefer a reputable grading report, and match the report to the stone
• Prioritize cut quality if you care about beauty
• If it is a major purchase, have an independent jeweler or gemologist verify it before your return window closes

If you want, tell me the carat, shape, and any grades you have (or a photo of the report), and I can give you a tight value checklist for that exact diamond.