Analytical Methords

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DIAMONDVIEW

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DIAMONDVIEW DiamondView as the name suggests, was developed by the Diamond Trading Company to screen diamonds for determination of natural and synthetic origin. The instrument basically is an imaging system, which uses the short-wave ultraviolet light below ~225 nm. The sample is targeted with the ultraviolet light and fluorescent reactions are observed through a CCD camera, which captures the fluorescent reactions and display them on the monitor through software. DiamondView not only assists in observing the fluorescence of the sample, but also its growth pattern as the CCD camera magnifies the sample, enabling to view the structure properly, against a gemmological ultraviolet lamp. The fluorescence image produced is of the surface or sub-surface up to few microns. It also assists in observing 'phosphorescence' of a sample. The fluorescent reactions not only indicate the presence of impurities but also the conditions in which a gem has formed. Therefore, the fluorescence i...
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LASER RAMAN SPECTROMETER (LRS)

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LASER RAMAN SPECTROMETER (LRS) Raman spectroscopy, as the name suggests is based on the Raman Effect discovered by the Indian physicist, Sir Chandrashekhar Venkata Raman (C. V. Raman) in 1928. Raman Effect takes place when monochromatic light (usually a visible laser) strikes a molecule and interacts with the bonds of that molecule. While most of the incident laser light scatters and produce no useful information (known as Rayleigh scattering), some of the light is re-emitted, which is shifted to longer wavelength with a loss of energy, known as 'Stokes radiation'. This shifted or stokes radiation produces a characteristic spectra or pattern of peaks, which can be considered as a 'fingerprint' for that substance.  Raman spectroscopy complements the infra red spectroscopy very well and provides useful information where FTIR fails to answer many questions. It is fast and non-destructive method of analysis without any sample preparation. In addition to the H2O or CO2 cont...
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Microscopy Role in Gems Testing

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Microscopy The microscope remains the most important tool in gem identification. A thorough and detailed analysis reveals a lot of information about a gem - it has a story to tell - about its origin - the depth within the earth's crust, the temperature and pressure conditions, the chemical environment in which it has formed, and much more. Observation of internal features is still the most valuable technique in identifying the nature of a gem. In some cases, the features are so characteristic, that they not only tell the identity of a gem, but also its origin. Microscopy remains the core of any gemmological study and complements 'the many' spectroscopic analytical tools, in determining the nature, whether natural or synthetic and the type and degree of treatments performed. At Shree Radhe Krishna International Gems Testing Laboratory, every analysis is started with a detailed microscopic observation. 
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