How the 4Cs drive price

Diamond prices are not linear. The same carat weight at different cut, colour, and clarity grades can vary by a factor of 5-10x. The most significant commercial price factors in order of commercial impact: carat weight (the largest single multiplier), cut grade (Excellent vs Good can differ 20-40%), colour grade (each step from D to G-H represents meaningful price differences), and clarity grade (VS2 to SI1 is the most commercially active range with the best value).

The Rappaport Diamond Report is the industry benchmark for diamond pricing, published weekly and used by dealers globally as the starting-point reference. Retail prices run above Rappaport; dealer-to-dealer prices run at or below. Online retailers typically run at -25% to -5% of Rappaport for GIA-certified round brilliants; retail jewellers may run at Rappaport or above.

Representative price ranges (GIA-certified round brilliant, 2024-25)

CaratG/VS2 ExcellentG/SI1 ExcellentH/SI1 Very Good
0.50 ctUSD 1,200-1,800USD 900-1,400USD 700-1,100
1.00 ctUSD 5,000-8,000USD 3,500-5,500USD 2,500-4,000
1.50 ctUSD 9,000-14,000USD 6,500-10,000USD 4,500-7,500
2.00 ctUSD 18,000-28,000USD 13,000-20,000USD 9,000-15,000

Approximate 2024-25 online retail ranges for GIA-certified Excellent cut round brilliants. Prices fluctuate with Rappaport benchmarks. Fancy shapes typically 15-30% below round at equivalent specs.

Where to buy for value

Online retailers (James Allen, Blue Nile, Whiteflash, Brilliant Earth) typically offer GIA-certified round brilliants at 20-35% below equivalent brick-and-mortar retail. The GIA certificate defines the quality; the price difference is the efficiency of the online channel. For local in-store purchase, compare the GIA certificate grade against the online price for that grade before agreeing a price. See the buying channel guide for a full comparison.

Sources

  • Rappaport Diamond Report. Industry price benchmark. rapaport.com.
  • GIA. Diamond grading standards. gia.edu.