SPINEL MAHENGE
13.15ct, Tanzania (Mahenge)
GRS, MELIKIAN
13.15ct, Tanzania (Mahenge)
GRS, MELIKIAN
GEMOLOGICAL REPORT № 146
Gemologist Olga Melikian | WA: https://wa.me/79990437349 13/10/2026
Telegram: @olgamelikianofficial | https://melikianjewelry.com
Weight: ……………………………..…………………..…….. 13.15 ct
Measurements: ……………….….………… 14.14x12.50x9.08 mm
Сut: ……………………………………………..………….…. cushion
Color / Color saturation: …….…. vivid red | strong color saturation
Clarity: …………………….………….……………… slightly included
IDENTIFICATION: ………………………………… Natural SPINEL
TRADE NAME: ……………………..………… SPINEL MAHENGE
Geographic Origin: ……………………..……… Tanzania (Mahenge)
Treatment: ……………………..………. No indication of treatment
Information about RED SPINEL MAHENGE:
The red spinel from Mahenge is the rarest and most expensive of all spinel varieties in Tanzania. The best specimens have a vivid red color and a large carat weight (10 carats or more).
RESULTS OF DIAGNOSTIC METHODS
10x glass: ………..………………………………………………………
There are gas-liquid inclusions, negative crystals, no cracks or
planar fractures, the stones spike and pavilion are undamaged, no
chips. 100% transparency. The quality of the cut is very good.
Refractive Index: ……………………………………………….… 1.722
Polariscope: ………………………………..…………..…….. isotropic
Dichroscope: ………………………………….……… no pleochroism
UV fluorescence: ………….………strong orangish red fluorescence
Chelsea Filter: …………………………….……………………….…….
Color change | Alexandrite effect (daylight | artificial light): ……. no
Microscope: No indication of treatment (fillers, heating). There are gas-liquid inclusions, negative crystals
Special properties:
Opalescence | adularescence | iridescence ………………………No
Cats eye effect…………………………………………….……….…No
Asterism……………………………………….………………………No
Gemologist Olga Melikian | WA: https://wa.me/79990437349 13/10/2026
Telegram: @olgamelikianofficial | https://melikianjewelry.com
Weight: ……………………………..…………………..…….. 13.15 ct
Measurements: ……………….….………… 14.14x12.50x9.08 mm
Сut: ……………………………………………..………….…. cushion
Color / Color saturation: …….…. vivid red | strong color saturation
Clarity: …………………….………….……………… slightly included
IDENTIFICATION: ………………………………… Natural SPINEL
TRADE NAME: ……………………..………… SPINEL MAHENGE
Geographic Origin: ……………………..……… Tanzania (Mahenge)
Treatment: ……………………..………. No indication of treatment
Information about RED SPINEL MAHENGE:
The red spinel from Mahenge is the rarest and most expensive of all spinel varieties in Tanzania. The best specimens have a vivid red color and a large carat weight (10 carats or more).
RESULTS OF DIAGNOSTIC METHODS
10x glass: ………..………………………………………………………
There are gas-liquid inclusions, negative crystals, no cracks or
planar fractures, the stones spike and pavilion are undamaged, no
chips. 100% transparency. The quality of the cut is very good.
Refractive Index: ……………………………………………….… 1.722
Polariscope: ………………………………..…………..…….. isotropic
Dichroscope: ………………………………….……… no pleochroism
UV fluorescence: ………….………strong orangish red fluorescence
Chelsea Filter: …………………………….……………………….…….
Color change | Alexandrite effect (daylight | artificial light): ……. no
Microscope: No indication of treatment (fillers, heating). There are gas-liquid inclusions, negative crystals
Special properties:
Opalescence | adularescence | iridescence ………………………No
Cats eye effect…………………………………………….……….…No
Asterism……………………………………….………………………No
DETAILED GEMOLOGICAL COMMENT
To accurately determine the mining region, the gem report should be supplemented with Raman microscope study, obtaining the spectrum of this Red spinel, and comparing it with the base spectrum of Red spinel from Tanzania.
The characteristics of this Red spinel:
Weight: ……………………………..…………………..…….. 13.15 ct
Measurements: ……………….….………… 14.14x12.50x9.08 mm
Сut: ……………………………………………..………….…. cushion
Color / Color saturation: …….…. vivid red | strong color saturation
Clarity: …………………….………….……………… slightly included
Geographic Origin: …………………………….…………… Tanzania
Treatment: …………………….….……. No indication of treatment
To accurately determine the mining region, the gem report should be supplemented with Raman microscope study, obtaining the spectrum of this Red spinel, and comparing it with the base spectrum of Red spinel from Tanzania.
The characteristics of this Red spinel:
Weight: ……………………………..…………………..…….. 13.15 ct
Measurements: ……………….….………… 14.14x12.50x9.08 mm
Сut: ……………………………………………..………….…. cushion
Color / Color saturation: …….…. vivid red | strong color saturation
Clarity: …………………….………….……………… slightly included
Geographic Origin: …………………………….…………… Tanzania
Treatment: …………………….….……. No indication of treatment