(IDEX Online) - October saw further downward pressure on prices, with decreases substantially outnumbering increases in both rounds and fancy cuts.

Rounds recorded 267 price decreases against 75 increases.

Fancy cuts recorded 253 decreases and 134 increases.

Rounds showed the clearest and broadest downward pressure in the middle sizes. Decreases dominated from 0.40-0.44 ct. through 1.50-1.99 ct., with particularly consistent weakness across the 0.70-0.79 ct. and 1.00-1.99 ct. bands.

The smallest rounds were more mixed: increases outnumbered decreases in the 0.18-0.22 ct., 0.23-0.29 ct. and 0.30-0.39 ct. categories, while 0.50-0.69 ct. recorded increases only.

At the larger end, 2.00-2.99 ct., 4.00-4.99 ct. and 5.00-5.99 ct. remained weighted toward decreases, but 3.00-3.99 ct. was an exception, with increases dominating.

The October tables therefore point to a market in which lower asking prices remained the prevailing direction, but not a uniform one. The clearest weakness was concentrated in rounds across the middle size ranges and in fancy cuts below 2.00 ct.

Pockets of upward movement, particularly among the smallest rounds and selected larger fancy cuts, underline the variation by size and cut.

Fancy cuts also showed a strong downward bias, especially in smaller and mid-sized stones. Decreases dominated from 0.18-0.22 ct. through 0.30-0.39 ct., and again across most categories from 0.50-0.69 ct. to 1.50-1.99 ct.

The pattern was not universal: 0.40-0.44 ct. and 0.45-0.49 ct. recorded more increases than decreases, while the largest categories, 4.00-4.99 ct. and 5.00-5.99 ct., also showed increases.

Overall, the breadth of declines was greater in rounds, while fancy cuts had more categories in which increases offset or outweighed decreases.

Rounds

0.18-0.22 ct. Increases slightly outnumbered decreases; N / I1 -25.0%, N / I2 -25.0%, M / I1 -20.0%; L / I3 +25.0%; J / I3 +20.0%.

0.23-0.29 ct. Increases dominated; M / I2 -16.7%, L / I2 -14.3%; N / I1 +20.0%; L / I3 +20.0%.

0.30-0.39 ct. Increases only; N / SI1 +9.1%; M / SI1 +8.3%.

0.40-0.44 ct. Decreases dominated; N / I3 -14.3%, N / I2 -11.1%, N / I1 -10.0%; K / VS1 +4.3%.

0.45-0.49 ct. Decreases slightly outnumbered increases; N / I3 -12.5%, N / VVS2 -4.3%; F / I3 +6.2%.

0.50-0.69 ct. Increases only; D / I2 +3.0%.

0.70-0.79 ct. Decreases only; D / VVS1 -4.7%, E / IF -4.6%, E / VVS1 -3.4%.

0.80-0.89 ct. Decreases dominated; G / I3 -4.5%, D / VVS1 -3.8%, G / IF -3.3%; F / IF +1.5%.

0.90-0.99 ct. Decreases dominated; N / VVS1 -4.5%, F / I1 -3.7%, H / SI3 -3.4%; H / I1 +4.0%; G / I1 +4.0%.

1.00-1.24 ct. Decreases dominated; D / VS1 -3.2%, D / VVS2 -2.9%, F / VS1 -1.8%; J / SI3 +3.1%; E / VVS1 +1.4%.

1.25-1.49 ct. Decreases dominated; F / VS2 -5.3%, E / VS2 -4.9%, F / VVS1 -4.4%; I / I2 +5.0%; L / I1 +4.0%.

1.50-1.99 ct. Decreases dominated; M / I2 -5.9%, L / I2 -5.9%, N / I2 -5.9%; N / SI3 +3.8%; E / VVS2 +3.4%.

2.00-2.99 ct. Decreases dominated; H / SI3 -4.3%, G / SI2 -3.8%, E / SI1 -3.4%; D / VVS2 +1.9%; L / VVS2 +1.8%.

3.00-3.99 ct. Increases dominated; N / I1 -6.5%, M / SI2 -5.8%, F / SI1 -2.4%; L / SI2 +3.4%; E / VS1 +3.1%.

4.00-4.99 ct. Decreases dominated; L / SI2 -4.4%, H / VS2 -4.1%, M / I2 -3.8%; I / I2 +3.1%; K / SI2 +3.1%.

5.00-5.99 ct. Decreases dominated; F / I3 -4.8%, D / I1 -3.9%, E / VS2 -3.8%; I / I2 +3.0%; I / VVS2 +2.8%.

Fancy Cuts

0.18-0.22 ct. Decreases dominated; N / I3 -50.0%, N / I1 -50.0%, N / I2 -50.0%; J / I2 +20.0%; I / I2 +16.7%.

0.23-0.29 ct. Decreases only; J / SI3 -10.0%, F / I2 -10.0%, E / I2 -10.0%.

0.30-0.39 ct. Decreases only; N / I1 -16.7%, M / I1 -14.3%, G / I2 -10.0%.

0.40-0.44 ct. Increases slightly outnumbered decreases; K / SI2 -5.3%, K / SI1 -5.0%, K / VS2 -4.8%; M / SI2 +18.2%; N / I1 +14.3%.

0.45-0.49 ct. Increases dominated; K / SI2 -4.8%, K / SI1 -4.5%, K / VS2 -4.3%; L / I1 +9.1%; J / I2 +9.1%.

0.50-0.69 ct. Decreases dominated; K / SI3 -4.8%, K / SI2 -4.3%, K / SI1 -4.2%; M / SI3 +6.7%.

0.70-0.79 ct. Decreases dominated; M / SI1 -4.5%, N / VS1 -4.3%, G / IF -3.4%; L / IF +2.7%.

0.80-0.89 ct. Decreases dominated; M / I3 -10.0%, D / VS1 -5.6%, M / I1 -5.6%; N / I1 +7.7%; K / SI1 +2.9%.

0.90-0.99 ct. Decreases dominated; M / I2 -12.5%, L / I1 -7.7%, K / SI3 -5.0%; L / SI3 +6.7%; E / IF +6.5%.

1.00-1.24 ct. Decreases dominated; M / I2 -10.0%, L / I2 -8.3%, N / VS1 -5.3%; N / SI3 +9.1%; N / SI1 +7.1%.

1.25-1.49 ct. Decreases dominated; M / I2 -9.1%, N / VS1 -9.1%, D / VS2 -5.4%; N / SI1 +12.5%; N / SI3 +7.7%.

1.50-1.99 ct. Decreases dominated; D / I1 -6.7%, F / SI3 -5.4%, E / SI3 -5.2%; H / IF +4.1%; D / VS2 +0.9%.

2.00-2.99 ct. Decreases dominated; D / IF -4.1%, K / SI2 -3.7%, H / SI2 -3.3%; H / IF +4.7%; I / I2 +4.3%.

3.00-3.99 ct. Mixed activity, with 22 increases and 22 decreases; L / VVS1 -4.7%, M / VVS1 -3.7%, D / VVS1 -3.5%; G / VS2 +4.5%; I / I2 +4.2%.

4.00-4.99 ct. Increases dominated; I / VS2 -4.8%, D / VS1 -4.0%, E / VVS2 -3.8%; G / VVS1 +4.1%; G / IF +3.9%.

5.00-5.99 ct. Increases dominated; D / VVS1 -4.2%, F / IF -4.1%, E / VS1 -4.1%; H / VS1 +4.3%; K / I2 +3.7%.

Basis of comparison: IDEX Diamond Price Reports dated 01 October 2026 and 01 November 2026. Percentages shown are month-on-month changes in the published asking-price tables.