The Diamond Guru: Fluorescence in HPHT Type I Diamonds

“Fluorescence Cage”:

Visual Identification of HPHT-Treated Type I Diamonds
Inga A. Dobrinets and Alexander M. Zaitsev

HPHT-treated type I diamonds of various colors may exhibit unusually intense fluorescence at the facet edges and junctions.

This effect, here named the “fluorescence cage,” is observed with a fluorescence microscope as a luminous network on the diamond’s surface.

It was not observed in untreated diamonds or colorless type IIa HPHT-treated diamonds. This fluorescence pattern is believed to result from a high concentration of HPHT-induced optical centers, which remain on facet edges after repolishing. Source GIA Fall 2009

Superior Quality Certified Diamonds

RBC 661 Round Brilliant 0.35 carat D VS2 Ex Ex Ex
4.59 min-4.61 max x 2.76 mm
GIA Cold Laser Inscribed #2106560475 AUD$1,397.00 GST Inclusive
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PRI 355 Princess Cut 1.30 carat E VVS1 Ex Ex
6.05 x 5.90 x 4.33 mm
GIA Cold Laser Inscribed #5106502726 AUD$15,730.00 GST Inclusive
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PRI 356 Princess Cut 1.40 carat F IF Ex VG
6.29 x 6.21 x 4.45 mm
GIA Cold Laser Inscribed #1109502745 AUD$18,524.00 GST Inclusive
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PRI 357 Princess Cut 1.46 carat E VVS2 Ex Ex
6.36 x 6.32 x 4.43 mm
GIA Cold Laser Inscribed #5106502750 AUD$17,006.00 GST Inclusive
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PRI 358 Princess Cut 0.50 carat D VVS2 Ex VG
4.54 x 4.46 x 3.05 mm
GIA Cold Laser Inscribed #1109535115 AUD$3,146.00 GST Inclusive
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PRI 359 Princess Cut 0.57 carat F VS2 Ex Ex
4.68 x 4.68 x 3.24 mm
GIA Cold Laser Inscribed #2106580158 AUD$2,233.00 GST Inclusive
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PRI 360 Princess Cut 0.46 carat F VS2 Ex Ex
4.37 x 4.29 x 2.95 mm
GIA Cold Laser Inscribed #1109554218 AUD$1,628.00 GST Inclusive
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PRI 361 Princess Cut 0.46 carat G VS2 Ex VG
4.43 x 4.35 x 2.91 mm
GIA Cold Laser Inscribed #1109544336 AUD$1,485.00 GST Inclusive
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PRI 362 Princess Cut 0.46 carat E SI1 VG VG
4.37 x 4.30 x 3.00 mm
GIA Cold Laser Inscribed # 1109553277 AUD$1,419.00 GST Inclusive
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FS 516 Cushion Brilliant 2.00 carats Fancy Vivid Yellow VVS1
Excellent polish Very Good symmetry
GIA cold laser incribed #2115126791 AUD$66,715.00 GST Inclusive
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FS 517 Cushion Brilliant 1.62 carats Fancy Intense Yellow IF
Excellent polish Very Good symmetry
GIA cold laser inscribed #1112153275 AUD$39,479.00 GST Inclusive

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FS 518 Pair Cushion Brilliant 1.34 carats Fancy Yellow VS2

Excellent polish Good symmetry

GIA cold laser inscribed #1112153276 AUD$14,597.00 GST Inclusive

FS 519 Pair Cushion Brilliant 1.33 carats Fancy Yellow VS2

Excellent polish Good symmetry

GIA cold laser inscribed #2115153290 AUD$14,487.00 GST Inclusive

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FS 521 Radiant Brilliant 0.29 carats Fancy Yellow IF

Excellent polish Very Good symmetry
GIA cold laser inscribed #5111153926 AUD$1,276.00 GST Inclusive

PRI 354 Princess Brilliant 1.40 carats I VS2

Excellent polish Very Good symmetry

GIA cold laser inscribed #5106510701 AUD$9,867.00 GST Inclusive
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FS 520 Cushion Brilliant 0.91 carats D VS1
Excellent polish Very Good symmetry
GIA cold laser inscribed #1109547630 AUD$7,073.00 GST Inclusive
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RBC 657 Round Brilliant 0.72 carats H VS2 Ex Ex Ex

GIA cold laser inscribed #5106498214 AUD$3,410.00 GST Inclusive
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RBC 658 Round Brilliant 0.81 carats H SI1 Ex Ex Ex
GIA cold laser inscribed # 5106496969 AUD$4,609 GST Inclusive
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RBC 659 Round Brilliant 0.86 carats I SI1 Ex Ex Ex
GIA cold laser inscribed # 5106496940 AUD$4,455.00 GST Inclusive
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RBC 660 Round Brilliant 0.39 carats D VVS1 Ex Ex VG
GIA cold laser inscribed # 2111038259 AUD$2,420.00 GST Inclusive
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