Price differences for surveyed diamonds

LAST UPDATE ON: April 13th, 2023

Table 3. Average cost of all 17 stones based on their grading and the premium or discount^[1] that their certificates attract.

Stone #	GIA-GTL	AGSL		EGL USA
Stone #	Price	Price	Diff. to GIA	Price	Diff. to GIA
1	$2,576	$2,296	-11%	$2,458	-5%
2	$2,922	$2,922	0%	$2,758	-6%
3	$4,248	$4,426	4%	$3,634	-14%
4	$4,540	$4,541	0%	$3,925	-14%
5	$1,522	$1,456	-4%	$1,527	0%
6	$1,496	$1,964	31%	$1,478	-1%
7	$2,075	$1,915	-8%	$1,707	-18%
8	$1,607	$1,501	-7%	$1,569	-2%
9	$2,058	$2,219	8%	$1,696	-18%
10	$2,453			$2,212	-10%
11	$2,952	$2,668	-10%	$2,624	-11%
12	$2,653	$2,398	-10%	$2,103	-21%
13	$2,152	$2,152	0%	$2,137	-1%
14	$4,127	$5,907	43%	$4,716	14%
15	$8,451	$7,264	-14%	$6,739	-20%
16	$8,255	$7,708	-7%	$6,323	-23%
17	$2,246	$2,047	-9%	$1,892	-16%
Average	$3,314	$3,337	1%	$2,912	-10%

Stone #
1
GIA-GTL Price	$2,576
AGSL Price	$2,296
AGSL Diff. to GIA	-11%
EGL USA Price	$2,458
EGL USA Diff. to GIA	-5%
2
GIA-GTL Price	$2,922
AGSL Price	$2,922
AGSL Diff. to GIA	0%
EGL USA Price	$2,758
EGL USA Diff. to GIA	-6%
3
GIA-GTL Price	$4,248
AGSL Price	$4,426
AGSL Diff. to GIA	4%
EGL USA Price	$3,634
EGL USA Diff. to GIA	-14%
4
GIA-GTL Price	$4,540
AGSL Price	$4,541
AGSL Diff. to GIA	0%
EGL USA Price	$3,925
EGL USA Diff. to GIA	-14%
5
GIA-GTL Price	$1,522
AGSL Price	$1,456
AGSL Diff. to GIA	-4%
EGL USA Price	$1,527
EGL USA Diff. to GIA	0%
6
GIA-GTL Price	$1,496
AGSL Price	$1,964
AGSL Diff. to GIA	31%
EGL USA Price	$1,478
EGL USA Diff. to GIA	-1%
7
GIA-GTL Price	$2,075
AGSL Price	$1,915
AGSL Diff. to GIA	-8%
EGL USA Price	$1,707
EGL USA Diff. to GIA	-18%
8
GIA-GTL Price	$1,607
AGSL Price	$1,501
AGSL Diff. to GIA	-7%
EGL USA Price	$1,569
EGL USA Diff. to GIA	-2%
9
GIA-GTL Price	$2,058
AGSL Price	$2,219
AGSL Diff. to GIA	8%
EGL USA Price	$1,696
EGL USA Diff. to GIA	-18%
10
GIA-GTL Price	$2,453
AGSL Price
AGSL Diff. to GIA
EGL USA Price	$2,212
EGL USA Diff. to GIA	-10%
11
GIA-GTL Price	$2,952
AGSL Price	$2,668
AGSL Diff. to GIA	-10%
EGL USA Price	$2,624
EGL USA Diff. to GIA	-11%
12
GIA-GTL Price	$2,653
AGSL Price	$2,398
AGSL Diff. to GIA	-10%
EGL USA Price	$2,103
EGL USA Diff. to GIA	-21%
13
GIA-GTL Price	$2,152
AGSL Price	$2,152
AGSL Diff. to GIA	0%
EGL USA Price	$2,137
EGL USA Diff. to GIA	-1%
14
GIA-GTL Price	$4,127
AGSL Price	$5,907
AGSL Diff. to GIA	43%
EGL USA Price	$4,716
EGL USA Diff. to GIA	14%
15
GIA-GTL Price	$8,451
AGSL Price	$7,264
AGSL Diff. to GIA	-14%
EGL USA Price	$6,739
EGL USA Diff. to GIA	-20%
16
GIA-GTL Price	$8,255
AGSL Price	$7,708
AGSL Diff. to GIA	-7%
EGL USA Price	$6,323
EGL USA Diff. to GIA	-23%
17
GIA-GTL Price	$2,246
AGSL Price	$2,047
AGSL Diff. to GIA	-9%
EGL USA Price	$1,892
EGL USA Diff. to GIA	-16%
Average
GIA-GTL Price	$3,314
AGSL Price	$3,337
AGSL Diff. to GIA	1%
EGL USA Price	$2,912
EGL USA Diff. to GIA	-10%

Figure 3. Price differences compared to similar GIA-GTL graded diamonds. Each positive or negative difference on the chart corresponds to higher or lower prices for similar diamonds listed for sale with respective reports.

fig4a fig4b
Figure 4. 56% of the surveyed diamonds would cost less if sold with AGS rather than GIA reports, mainly as a result of stricter clarity grading 80% of the diamonds would cost less if bought with EGL rather than GIA reports. Discounting of EGL graded diamonds was greater than any premiums as a result of softer color grading.