News
S.
Gemmological Institute SSEF
Dr. Michael
Krzemnicki Swiss
Photos
© M.S. Krzemnicki,
SSEF, except where indicated otherwise SSEF
SGG Zentralkurs in Meisterschwanden Dienstag 21 April 2015
New SSEF office since January 2015: Aeschengraben 26 4051 Basel © Swiss Gemmological Institute SSEF
Jadeite
with
chromium-rich vein g W eng h ] A orban e A U] W be A o ban n :\D TA K Feb 2015 FT R\sili ade 8695 78695_5_ ade ck 78695_5_jade ck st ty and 26 02 201 P g 1 1 Cr-rich
veins are common in jadeite from Myanmar
© Swiss Gemmological Institute SSEF© T. Cheng
in'jadeite0like cutting'&' setting
Emerald with engraving of Catherine the Great
Comparing'this' engraved'portrait' with'historic' paintings'shows'a' very'close' resemblance,'notably' with'the'portraits'of' the'Catherine'the' Great'(1729'–'1796')' Empress of the Russian'Empire'by' William'Dickinson' (from'1773)'and' Virgilius Erichsen (from'1830),'both' being'part'nowadays' of'the'State' Hermitage'Museum' in'Saint'Petersburg' (Russia).'
Brazilian emerald
© Swiss Gemmological Institute SSEF
Jadeite'necklace'and'ring.'
Fe2+ octahedral sites of
(820%nm)%causes
40, halogen W avelength [nm] 1,000900800700600500400 A b s orban c e [ A U] 0 emerald with distinct aquamarine-component © Swiss Gemmological Institute SSEF
the beryl,%(8108830%nm)%no colour Fe2+%in%the structural channels
blue colour Bluish green Cr-bearing beryl with dominating aquamarine-component © Swiss Gemmological Institute SSEF 3004005006007008009001000 The%bands%370%and 420%nm%due%to octahedral%Fe3+ and induce%a%yellowish (greenish)%colour Fe2+%in%the structural channels (820%nm)% causes the blue colour 54.84%ct
AvaSof 7 3 1 Avantes 78887_emera d 9 456ct, t 100 avg 40 Curren W ave ength 602 796 nm Wavelength [nm] 900850800750700650600550500450400350300 A b s orban c e [ A U] 1 0 Bluish green emerald with no aquamarine-component © Swiss Gemmological Institute SSEF Bluish green colour%due%to absence of%Fe3+%in%octahedral sites resulFng%in%transmission8 window%in%the blue%(and%LWUV)% Very low%Fe2+% in%octahedral sites and%in% the structural channels:% No colour contribuFon 9.46%ct Hydrothermal synthetic emerald of 67 ct © Swiss Gemmological Institute SSEF
Emerald imitation: Foiled back topaz
La Belle of Asia… © Swiss Gemmological Institute SSEF Historical%sapphire from%Ceylon%of%392.52%ct Sold%at aucFon%in%November%2014,%World%record%$17,295,796% SSEF%report no.%72359%
Exceptional Kashmir sapphires
© Swiss Gemmological Institute SSEF
Highly'matching' in'colour'and' outstanding' clarity'
Photo: Sutas Singbamroon
BYG Sapphires from basaltic deposits
©!GIA http://www.gia.edu future! after! visiting the new!sapphire!mining!area!and! completing!a! study!of!the samples! collected!on!site at!the!time ©!GI http://www.gia.edu August!16th,!201 Figure' 4:'Local'map'(modified'from'Google'Earth)' of'the'Mambilla'Plateau'area'with'the'approximate'location'of'the'new' deposit shown, near'Guroji'according'to'the'information'provided'by'local'miners .'The'old'diggings'producing'small'dark'blue' stones'seem to'be'located'near'Gembu' close'to'the' he'exact'location'of'these'deposits'still' be'confirmed.'Note:'The'photos'of'the'single'stones' of one'stone' reportedly'from' the' new'deposit, and'another' courtesy'Brume'Jeroh Laboratory'Bangkok. Sadly!the! GIA!field! expedition! to!Nigeria! the!end!of!April! and! with! the! advent!of the! rainy!season!in!Nigeria,!it!was!difficult!to!plan!another!exped before!the!completion!of!this!report.!Thus!this! study will!only!be!a! “ based!on! F!type!samples!(per GIA!Field!Gemology!department! terminology means that!these!samples! were!collected!from! trustworthy West African! the!beginning! of!June!2014,!as!the!field!expedition!was!postponed, we! interesting! parcels of!fine!quality!rough!sapphires, reportedly!from! the!Mambilla!area to!start!a!preliminary!study!on! the new!material.! Our!plans!are to!confirm!these!result future! after! visiting the new!sapphire!mining!area!and! completing!a! collected!on!site at!the!time.! Photos & maps: V. Pardieu, 2014 5.58'ct Typical features of basaltic sapphires:' Often greenish blue colour Quite often distinct milkyness Fe0rich:'Characteristic absorption spectrum 0 Distinct'OH0'(hydroxyl)'in'IR'spectrum AvaSof 7 3 1 Avantes 76575_research_sapph re 5 577ct, n 40 avg 40 Curren W a e eng h 454 455 nm Wavelength [nm] 750700650600550500450400350300 A bso r bance [ A U ] 1 20002500300035004000 Wavenumber cm 1 0 8 5 0 9 0 0 9 5 1 0 0 A b s o r ban c e U n it s UV#Vis FTIR& 3309%cm81%
Ruby Heated ruby from Mozambique © Swiss Gemmological Institute SSEF Neo0healing']issure'charactersitic'for'heat'treatment'' (and'FTIR'peaks'at'3309'cm01'with'small'side'bands)'
Exceptional unheated ruby from Mozambique 23 ct 78805_ y t, g C W h 492 381 W eng h A b s orban e A U] 1 0
© Swiss Gemmological Institute SSEF
The%Sunrise%ruby,%a%25.59%ct%Burmese%ruby of%"pigeon's blood"%hue,% will%be offered at aucFon by Sotheby's Geneva%on%12%May%2015% with%an%esFmated value of%$12818million.% New world record for ruby ? Latest news&13th&May&2015:&& Sold&for&30.3&million&US$&
27 ct Burmese ruby in a historic setting
© Swiss Gemmological Institute SSEF
Padparadscha from Ceylon, 46 ct © Swiss Gemmological Institute SSEF A S 7 3 1 A 78933_o apph 46 919 t, 300 40 C W h 602 796 Wave eng h [nm 850800750700650600550500450403530 A b s orban c e A U] 0 Colour is%a%combinaFon of%Cr3+,%Fe3+ and yellow colour centre
Yellow sapphire with unstable colour
Heated spinel from Tanzania
Heat treatment rarely applied'on'spinels'so'far:' Only'limited'enhancement Colour change only slight Fine'milkyness is said to be reduced
Heated spinel from Tanzania AvaSo t 7 3 1 Avan es 76610 ed sp ne and re e ence o unhea ed red sp ne Curren Wave ength 683 179 nm 01: amp=9061.3 it=300.00 av=30 s=0 71196_0001.roh: 1305157U1- 71196, red spinel, 10.780ct, PL, IT=300ms, Avg=30 Wave eng h [nm] 760740720700680660640 C oun s 60 000 50 000 40 000 30 000 20 000 10 000 0 heated unheated Diamond wi(n)dow
