The DFI Mid-UV Laser + :

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Hainschwang 1) and Franck Notari 2) thomas.hainschwang@ggtl-lab.org franck.

1 The DFI Mid-UV Laser + : The solution for efficient and conclusive screening of mounted and unmounted D-Z colour diamonds of all shapes and all sizes Thomas Hainschwang 1) and Franck Notari 2) thomas.hainschwang@ggtl-lab.org franck.notari@ggtl-lab.org 1) GGTL Laboratories Liechtenstein 2) GGTL Laboratories Switzerland

DFI Mid-UV Laser + : The Instrument - DFI Mid-UV Laser + is an efficient screening instrument based on UV luminescence imaging and spectroscopy plus Raman spectroscopy.

2 DFI Mid-UV Laser + : The Instrument - DFI Mid-UV Laser + is an efficient screening instrument based on UV luminescence imaging and spectroscopy plus Raman spectroscopy. - 5 different UV excitation bands from 230 nm to 420 nm - 1 laser excitation - NOT automated - All sizes and shapes - Mounted and lose diamonds - Results usually directly in identification nat/synth/imit - Testing at RT and LNT possible

The DFI - Working Principles Distinction of diamonds, synthetic diamonds and imitations based on: 1) Luminescence color, intensity and distribution (Laser- or UV-induced), phosphorescence 2)

3 The DFI - Working Principles Distinction of diamonds, synthetic diamonds and imitations based on: 1) Luminescence color, intensity and distribution (Laser- or UV-induced), phosphorescence 2) Photoluminescence spectroscopy (Laser- or UV-excited, samples at room temperature or at liquid nitrogen temperature [77K]) 3) 405 nm laser Raman spectroscopy Luminescence imaging, PL and Raman spectroscopy are all done at the same time.

The DFI - Capacities and Requirements 1) After a three to five day training a technician can solve virtually all problems in D-Z colour diamond screening.

4 The DFI - Capacities and Requirements 1) After a three to five day training a technician can solve virtually all problems in D-Z colour diamond screening. 2) After a few weeks of melee screening practice an average technician can work through 2500 to 3500 stones per hour. 3) Technician needs only common sense and some logic, no requirement for a degree in earth sciences or physics necessary. 4) Working at low temperature is straight forward, easy and not dangerous.

5 Advantages of Raman- and Luminescence- Based Techniques used by the DFI - Raman and luminescence spectroscopy, luminescence imaging. - Non-destructive methods. - Applicable for very small samples, nearly no size limitation. - For transparent and opaque stones of all shapes and sizes, loose or mounted in jewellery. - Typically much faster, sensitive and accurate than absorption or SWUV based methods. - Distinguishes natural diamonds from synthetics ad imitations, and identifies them directly. At room temperature only very few undeterminable stones, at low temperature practically no undeterminable stones.

DFI Screening VS Other Screening Systems Diamonds rejected via other systems (47 stones), all identified

3 stones isolated by DFI as well were the only type IIa and IIb diamonds in the parcel.

While other systems reject 50 samples as being potentially synthetic, the room temperature DFI

6 DFI Screening VS Other Screening Systems Diamonds rejected via other systems (47 stones), all identified as natural by room temperature DFI analysis. 3 stones isolated by DFI as well were the only type IIa and IIb diamonds in the parcel. Undeterminable at room temperature, but identified as natural by DFI at LNT. While other systems reject 50 samples as being potentially synthetic, the room temperature DFI luminescence based screening isolates only 3 stones, actually the only real type IIa and IIb diamonds out of the 50 stones. By low temperature DFI testing these three samples are equally identified as natural diamonds.

7 APPLICATION EXAMPLES

8 The DFI Fluorescence Imaging: Natural Diamond

9 The DFI Fluorescence Imaging and Spectroscopy: Natural Diamonds

10 The DFI Fluorescence Imaging and Spectroscopy: As-grown HPHT Synthetic Diamond First and second order Raman 880 nm Nickel defects

11 The DFI Fluorescence Imaging and Spectroscopy: As-Grown CVD Synthetic Diamond

12 The DFI Fluorescence Imaging and Spectroscopy: HPHT Treated CVD Synthetic Diamond

13 The DFI Raman Spectroscopy: Diamond VS Imitations

14 Technical Data and Available Options Excitation sources Microscope Camera Spectrometer High power broadband source filtered to permit up to 6 different UV excitation bands. High power 405 nm violet laser. Leica Trinocular Microscope, 7.5 to 70x. Leica CCD camera with 5 megapixel resolution and thermoelectrically cooled detector. Standard configuration CCD Type, irradiance calibrated Czerny-Turner spectrometer with cooled detector, spectral range 200 to 1100 nm, resolution 1.3 nm. 5 different excitation bands and 1 laser, single channel spectrometer, setup for room and low temperature imaging and spectroscopy, accessories and five day training for room and low temperature photoluminescence spectroscopy and imaging. Weights and dimensions: 70 kilograms total weight; dimensions (L x W x H): 70 x 60 x 90 cm Available options Multichannel spectrometer for higher resolution spectroscopy. Extended spectral Database with two years updates One additional excitation band of choice. Spectral database for room temperature spectroscopy or low temperature spectroscopy.

15 Support and Database - Quasi-permanent support by Dr Thomas Hainschwang and Franck Notari. - Extended Database, with scientific documentation, with commented and indexed spectra and reference spectra in.irr8 format. Two years updates included. - Our policy is to support and help our customers as efficiently as possible according to their specific needs.

16 GGTL Laboratories, 2016

Chemistry 524--Final Exam--Keiderling May 4, :30 -?? pm SES

Chemistry 524--Final Exam--Keiderling May 4, 2011 3:30 -?? pm -- 4286 SES Please answer all questions in the answer book provided. Calculators, rulers, pens and pencils are permitted. No open books or