Whether it's your first diamond or your fifth, the rules are the same: a great stone is one you understand. Here's what every page on this site is really pricing.
The 4 Cs
Carat
Weight, not size. One carat is 0.2 grams. The same carat weight can look bigger or smaller depending on the shape and how the stone was cut. Round-brilliant 1.00 ct ≈ 6.4 mm across the top.
Color
D is the rarest (totally colorless), then E and F (still colorless to the eye), then G–J (near-colorless). Once you set a diamond in a ring, most people can't tell D from G. Our inventory leans heavily into D–F because the cost difference is small at lab-grown prices.
Clarity
The number, size, and position of internal inclusions and surface blemishes. The scale runs FL → IF → VVS1 → VVS2 → VS1 → VS2 → SI1 → SI2 → I1 → I2. VS1 and above are "eye-clean" — you can't see any inclusion without a loupe. We don't sell anything below VS1.
Cut
The most under-rated C and the one that actually controls how a diamond sparkles. Cut grade is Excellent, Very Good, Good, Fair, Poor. We list "EX" (Excellent) by default — anything less and we wouldn't ship it.
Lab-grown vs mined
A lab-grown diamond is the same crystal structure, the same hardness, the same chemistry as a mined diamond. The difference is the address where it grew. Lab-grown stones are graded by the International Gemological Institute (IGI) — the standard certification body for lab-grown — on the same 4 Cs scale used everywhere else in the industry.
What changed is the price. Lab-grown wholesale prices have come down dramatically — which is the entire reason DiamondDealz exists.
Reading a certificate
Every stone in our catalog ships with an IGI lab report. The report includes:
- A unique report number — verifiable on the lab's website.
- The 4 Cs as graded by the lab, not the seller.
- A plot of inclusions and any laser inscription on the stone's girdle.
- Measurements: length × width × depth in millimeters.
Match the report number on the certificate to the laser-inscribed number on the diamond. If they line up, you have what you paid for.