I Colour

Live pricing and availability for I colour diamonds across natural and lab-grown origins.

Total listings
1,247,457
Natural median (NZD)
$3,683/ct
Lab-grown median (NZD)
$2,321/ct

What I Colour Means for Buyers

I sits on the GIA colour scale that runs from D (colourless) at the top through to Z (faint yellow or brown). The higher up you go toward D, the rarer the stone and the steeper the price curve. But a huge number of buyers never tell the difference between two adjacent grades in a finished ring, especially once the diamond is mounted in yellow or rose gold.

Right now we're tracking 1,247,457 active I colour listings across our retailer network. The typical natural I diamond trades around $3,683/ct while the lab-grown equivalent sits at $2,321/ct. Roughly a 37% gap that reflects the broader natural-vs-lab pricing gap, not a quality difference at this grade.

I commands a modest 8.3% premium over the neighboring J grade. For buyers who prioritise face-up appearance over spec sheets, J delivers almost all of the visual quality for noticeably less. Pay for I only if you care about the grade showing on the cert.

I shows up most often in ROUND. About 569,246 listings at this moment. Followed by OVAL. Most of the supply clusters around the 0.5-0.99ct carat range, where demand is strongest and retailers keep the deepest inventory. If you're shopping an unusual shape or carat, expect thinner selection.

For most engagement-ring buyers, the practical sweet spot for colour is G or H. Colourless-appearing face-up, still a near-colourless grade on paper, and priced 30 to 50% below the D-E tier. If you're setting the stone in yellow or rose gold, you can comfortably go down to I or J without the stone looking warm. Save the money for a better cut grade; cut drives sparkle far more than the last step of colour.

Breakdown by Shape

ShapeOriginListingsMedian (NZD)
ROUNDnatural569,246$3,396/ct
OVALnatural130,250$4,306/ct
EMERALDnatural100,198$3,933/ct
PEARnatural96,878$3,771/ct
ROUNDlab grown76,849$2,535/ct
CUSHIONnatural55,384$4,554/ct
PRINCESSnatural49,929$3,847/ct
HEARTnatural43,362$3,685/ct
RADIANTnatural27,693$4,158/ct
ASSCHERnatural23,893$3,921/ct
MARQUISEnatural21,669$3,731/ct
OVALlab grown14,175$2,498/ct
PEARlab grown13,870$2,071/ct
EMERALDlab grown7,793$1,474/ct
PRINCESSlab grown3,664$2,093/ct
CUSHIONlab grown3,398$1,672/ct
RADIANTlab grown2,989$1,551/ct
MARQUISElab grown1,839$2,199/ct
HEARTlab grown1,705$1,828/ct
OTHERnatural1,163$5,035/ct
ASSCHERlab grown888$1,472/ct
TRILLIONnatural452$5,831/ct
OTHERlab grown204$779/ct
BAGUETTEnatural135$6,054/ct
ROUNDunknown43$2,577/ct
BAGUETTElab grown37$849/ct
SQ_RADIANTnatural26$2,201/ct
TRILLIONlab grown18$925/ct

Breakdown by Carat

CaratOriginListingsMedian (NZD)
0.5-0.99ctnatural393,756$2,737/ct
0.5-0.99ctlab grown32,430$2,757/ct
0.5-0.99ctunknown2$3,702/ct
1.0-1.49ctnatural263,082$4,700/ct
1.0-1.49ctlab grown18,856$2,480/ct
1.0-1.49ctunknown6$5,429/ct
1.5-1.99ctnatural137,078$7,153/ct
1.5-1.99ctlab grown24,935$1,896/ct
1.5-1.99ctunknown4$9,831/ct
2.0-2.99ctnatural82,210$11,079/ct
2.0-2.99ctlab grown22,781$2,182/ct
2.0-2.99ctunknown1$10,924/ct
3.0ct+natural38,774$20,688/ct
3.0ct+lab grown15,921$2,093/ct
3.0ct+unknown1$26,776/ct
under-0.5ctnatural205,378$2,450/ct
under-0.5ctlab grown12,508$2,602/ct
under-0.5ctunknown34$2,321/ct
Back to all Colour grades
Search diamonds by gradeAsk Lucy

Compare prices across 100+ retailers worldwide. Find the best deal on your perfect diamond.