I Colour

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

Total listings
1,483,120
Natural median (NZD)
$3,673/ct
Lab-grown median (NZD)
$2,318/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 1,483,120 active I colour listings across our retailer network. The typical natural I diamond trades around $3,673/ct while the lab-grown equivalent sits at $2,318/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 7.6% 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 725,527 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)
ROUNDnatural725,527$3,332/ct
OVALnatural143,494$4,341/ct
EMERALDnatural120,565$3,832/ct
PEARnatural114,865$3,738/ct
CUSHIONnatural72,974$5,133/ct
ROUNDlab grown67,305$2,564/ct
PRINCESSnatural56,122$3,884/ct
HEARTnatural40,514$3,601/ct
RADIANTnatural36,859$4,692/ct
MARQUISEnatural32,748$3,873/ct
ASSCHERnatural25,607$4,213/ct
PEARlab grown12,405$2,060/ct
OVALlab grown11,763$2,464/ct
EMERALDlab grown7,244$1,584/ct
CUSHIONlab grown3,529$1,683/ct
PRINCESSlab grown3,263$2,280/ct
RADIANTlab grown2,601$1,531/ct
MARQUISElab grown1,667$2,241/ct
OTHERnatural1,229$5,497/ct
HEARTlab grown979$2,065/ct
ASSCHERlab grown466$1,831/ct
TRILLIONnatural454$5,937/ct
OTHERlab grown245$798/ct
BAGUETTEnatural144$6,182/ct
SQ_RADIANTnatural62$4,465/ct
ROUNDunknown37$2,509/ct
BAGUETTElab grown36$963/ct
TRILLIONlab grown17$1,822/ct

Breakdown by Carat

CaratOriginListingsMedian (NZD)
0.5-0.99ctnatural471,459$2,749/ct
0.5-0.99ctlab grown26,116$2,753/ct
0.5-0.99ctunknown2$2,971/ct
1.0-1.49ctnatural302,227$4,767/ct
1.0-1.49ctlab grown15,545$2,296/ct
1.0-1.49ctunknown2$5,074/ct
1.5-1.99ctnatural167,031$7,286/ct
1.5-1.99ctlab grown23,067$2,037/ct
1.5-1.99ctunknown3$11,104/ct
2.0-2.99ctnatural102,373$11,440/ct
2.0-2.99ctlab grown22,135$2,263/ct
2.0-2.99ctunknown1$10,357/ct
3.0ct+natural49,559$20,929/ct
3.0ct+lab grown16,030$2,658/ct
3.0ct+unknown1$25,105/ct
under-0.5ctnatural278,515$2,387/ct
under-0.5ctlab grown8,629$2,832/ct
under-0.5ctunknown32$2,390/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.