News

By: Branko Deljanin (CGL Canadian Gemlab, Vancouver)

Introduction

Fancy colored diamonds are breaking all records at auctions for price paid per carat. Blue and red diamonds are considered the most expensive natural gems by weight in the world. Natural near-colorless diamonds originate from more than ten diamond-producing nations whose mines are owned by several big mining companies including Alrosa, De Beers and Rio Tinto. In addition, many other primary and alluvial deposits are sporadically mined by smaller companies in places like Brazil and Africa, even by family businesses.

If any of these mines ceased operation, it would likely not affect the world’s market value of near-colorless diamonds. In the case of pink diamonds, 90 percent of the world’s supply is mined from a single source, Rio Tinto’s Argyle Mine in Australia.

Although operations at Argyle are currently underground, the mine’s production life is expected to run until late 2020. This limitation, combined with the rarity of pink diamonds, are contributing factors to skyrocketing prices approaching 15 percent compound per annum over the past ten years.

The demand for pink diamonds has increased in part due to the following factors (Deljanin 2014):

• Exposure in mainstream media, most often in the form of famous celebrities buying pink diamonds as well as record-breaking prices at major auctions
• Australia’s strict adherence to the Kimberley Process and the proven conflict free Australian origin of Argyle pinks supported by effective marketing by Rio Tinto
• The overall rarity of pink diamonds compared to other colors
• Closure of Argyle diamond mine in late 2020

This article aims to give an overview of natural pink diamonds from seven major producing countries on four continents. We suggest establishing a new class of “Argyle-type pink diamonds” with characteristic features using standard and advanced gemological instruments.

Branko_Deljanin-May_June_2020-Provenance_of_Pink_Diamonds.pdf

By: Branko Deljanin (CGL Canadian Gemlab, Vancouver)

Introduction

Considering the occurrence of undisclosed lab-grown diamonds, vigilance combined with the use of standard and advanced gemmological tools are critical to ensure confidence in the supply line. While well-equipped labs can identify such non-natural origin and issue a report accordingly, diamond dealers, gemmologists, appraisers and retailers need instruments that help them to screen natural and some cases identify lab-grown diamonds. There are an increasing number of detection instruments and machines (see table 1 below) on the market that use different methods for screening/detection, notably:

• transparency to SW UV light
• characteristic fluorescent/phosphorescent reaction to LWUV, SWUV and other UV light
• Vis, PL, Raman, FTIR and fluorescence spectroscopy
• fluorescence imaging and other undisclosed techniques

Download Report

Comparison_of_portable_instruments_for_screening_and_ID_of_Lab-Grown_Diamonds.pdf

• Overview: Identifying Natural, Treated and Synthetic Diamonds with Standard and Advanced Instruments
• Instructor: Branko Deljanin, B.Sc., GG, FGA, DUG (Gemmological Research Industries Inc, Canada)
• Location: DMCC, Jumeirah Lakes Towers, Dubai, UAE
• Flyers:
  • 20191123-DUBAI_SEMINAR_DAY1.pdf
  • 20191124-DUBAI_SEMINAR_DAY2.pdf
  • 20191125-DUBAI_SEMINAR_DAY3.pdf

Day 1: November 23, 2019 (Saturday)
ID of Coloured Diamonds – Treated and Lab-grown

 

Day 3: November 25, 2019 (Monday)
Practical Intense Seminar: Screening & ID of Diamonds

Morning (9:00 AM to 12:45 PM): ID of Colourless Diamonds (Natural, Treated, and Lab-grown)

• Colourless Natural diamonds: sources, characteristics and identification
• Methods of growing HPHT and CVD diamonds
• Inclusions in Natural and Synthetic diamonds
• UV lamp – reaction of different diamonds, loose/mounted with “PL / Jewellery inspectors”)
• CPF (Cross Polarized Filters) method and to screen and ID diamond’s origin
• Clarity and Color Enhancements – unstable (Fracture Filling and coating),
• Clarity Enhancements – stable (Traditional Lasering, KM Laser drilling)
• Post treatments of CVD-grown colorless diamonds (by HPHT press)
• ID of HPHT-enhanced diamonds using advanced instruments
• ID of mounted synthetic diamonds with EXA instrument and screening instruments
• Problems and solution in identification of melee natural and synthetic diamonds

PRACTICAL: Samples of Ia, IIa, IIb, Ib diamonds (natural and synthetic origin) are tested with UV lamp (“inspectors”), Gempen, microscopes and Polarioscope, Alrosa Diamond Inspector, EXA.

Afternoon (1:45 PM to 5:30 PM): ID of Coloured Diamonds (Natural, Treated, and Lab-grown)

• YELLOW and ORANGE diamonds: sources/producers, characteristics and ID
• GREEN and CHAMELEON diamonds: source/producers, characteristics and ID
• BLUE and GRAY diamonds: sources/producers, characteristics and ID
• PINK and RED diamonds: sources/producers, characteristics and ID
• Use of Standard Instruments to separate Coloured Natural and Synthetic Diamonds
• Color Enhancements – stable (irradiation, annealing, HPHT, multistep treatments)
• Post treatments of HPHT-grown and CVD-grown diamonds (irradiation and HPHT)
• Identification methods for treated diamonds with advanced instruments at labs
• Grading and Certification of coloured diamonds at gem laboratories

PRACTICAL: Coloured Diamonds are tested with portable polarioscope, Gempen, PL Inspector, microscope and handheld spectroscope in screening and ID with EXA machine.

Instructor: Branko Deljanin, B.Sc., GG, FGA, DUG (CGL-GRS Lab, Canada)
Audience: For gemmologists, appraisers, and individuals with trade experience
Date: Aug 23, 2019 (Friday)
Location: Strand Golf course, Naples, Florida

9am-12:45pm: ID of Colourless Diamonds (Natural, Treated, and Lab-grown)

• Colourless Natural diamonds: sources, characteristics and identification
• Methods of growing HPHT and CVD diamonds
• Inclusions in Natural and Synthetic diamonds
• UV lamp – reaction of different diamonds, loose and mounted with “PL / Jewellery inspectors”)
• CPF (Cross Polarized Filters) method and to screen and ID diamond’s origin
• Clarity and Color Enhancements – unstable (Fracture Filling and coating),
• Clarity Enhancements – stable (Traditional Lasering, KM Laser drilling)
• Post treatments of CVD-grown colorless diamonds (HPHT)
• ID of HPHT-enhanced diamonds using advanced instruments
• ID of mounted synt. diamonds with EXA instrument and screening instruments
• Problems and solution in identification of melee natural and synthetic diamonds

PRACTICAL WORKSHOP: Samples of Ia, IIa, IIb, Ib diamonds (natural and synthetic origin) are tested with mini UV lamp (“PL inspector”), microscopes with mini Polarioscope

1:45pm-5:30pm: ID of Coloured Diamonds (Natural, Treated, and Lab-grown)

• YELLOW and ORANGE diamonds: sources/producers, characteristics and ID
• GREEN and CHAMELEON diamonds: source/producers, characteristics and ID
• BLUE and GRAY diamonds: sources/producers, characteristics and ID
• PINK and RED diamonds: sources/producers, characteristics and ID
• Use of Standard Instruments to separate Coloured Natural and Synthetic Diamonds
• Color Enhancements – stable (irradiation, annealing, HPHT, multistep treatments)
• Post treatments of HPHT-grown and CVD-grown diamonds (irradiation and HPHT)
• Identification methods for treated diamonds with advanced instruments at labs
• Grading and Certification of coloured diamonds at gem laboratories

PRACTICAL WORKSHOP: Coloured Diamonds are tested with portable polarioscope, PL Inspector, microscope and handheld spectroscope in screening and identification.

Instructor: Branko Deljanin, B.Sc., GG, FGA, DUG (CGL-GRS Lab, Canada)
Audience: For gemmologists, appraisers, and individuals with trade experience
Location: Brisbane, Australia
Date: Mar 14, 2019

MORNING (9.00am-12.45 pm): EMERALD 

Identification of Emeralds is still possible outside a lab because many gemstone properties can be analyzed with portable instruments. We will cover emerald’s identification, recognition of synthetics and understanding the difference between hydrothermal and flux synthetics, as well as the identification of fillers inside cracks. Oiling is an accepted treatment in the trade and today, and almost all emeralds are oiled / clarity enhanced. There is new deposit of emeralds in Ethiopia that has different characteristics than emeralds from Columbia, Brazil or East Africa

• Emerald Sources
• Identification of Fracture Filled Emeralds
• Synthetic Emeralds
• Use of Advanced Instruments in Detection and Certification at Gem Labs

AFTERNOON (13.45am-17.30 pm): JADE

Come to this lecture and workshop and learn how to screen for A jadeite jade (natural colour), B jade (impregnated with polymer) and C jade (dyed) using only UV lamp! You need to also know your limitations using standard instruments in testing jade and when piece of Jadeite or Nephrite Jade in question should be sent to gem laboratory for advanced testing with VIS-NIR and Infrared spectrometers.

• Properties of  Jadeite and Nephrite Jade
• Identification of Dyed Jadeite Jade with Microscopy and VIS spectroscopy
• Identification of Polymer Impregnated Jadeite Jade by FTIR Spectroscopy

PRACTICAL LAB SESSION

• Participants we will look at inclusions in emeralds from different localities, detection of oiled and synthetic emeralds with a microscope and loupe.
• Use of microscopy and fluorescence in detecting oiled emeralds and dyed jadeite jade
• Screening for Jade (A, B or C) with UV lamp (PL and Jewelry inspectors

Instructor: Branko Deljanin, B.Sc., GG, FGA, DUG (CGL-GRS Lab, Canada)
Audience: For gemmologists, appraisers, and individuals with trade experience
Location: Brisbane, Australia
Date: Mar 13, 2019

Full Day: 9:00am – 5:30pm

Historically ruby and sapphire are the most significant colored stones. Rubies are expected to have some inclusions because of their growing environment that can help with identification (natural, treated or synthetic). Heating is an accepted treatment in the trade and today, almost all but the finest rubies and sapphires are routinely heated.

Sapphires have some natural inclusions that in combination with spectroscopy can help identify a sapphire’s country of origin. Yellow, orange and blue sapphires can be heated with additional lighter elements to induce color. Lattice diffusion with beryllium is more permanent than traditional titanium diffusion treatment.

• Corundum Treatments
• Detection of Heat Treatments of Ruby and Sapphire
• Heat Treatments with Chemical Elements
• Effect of Heat Treatments on Inclusions
• Synthetic Rubies and Sapphires
• Use of Advanced Instruments in Detection of Treatments and Synthetics
• Certification of Rubies and Sapphires at Gem Labs

PRACTICAL LAB SESSION

• Separation of  ruby  and other red gems using standard portable instruments
• Use of microscopes and UV lamps for detection of rubies and sapphires
• Participants we will look at inclusions in ruby, sapphire and emeralds from different localities, detection of heat treatments and lead glass-filled rubies and oiled emeralds with a microscope
• Different fluorescence reactions of red gems and sapphire will be examined with PL Inspector

Tools to bring home: handouts, NEW booklet “ID of Transparent Red, Pink and Purple Gems with Portable Instruments” by Branko Deljanin, John Chapman, 30AUS value

Available for sale: books, CPF loupe, Jewellery and PL inspectors