GAAJ-ZENHOKYO Research Lab Equipment

The state of the art research laboratory boasts many firsts in the field technical equipment and research findings.  GAAJ-ZENHOKYO was the first gemmological lab to operate the Ramanscope system which is used to detect HPHT treatments.  It was also the front runner for the use of the LA-ICP-MS analysis instrument and the Laser Induced Breakdown Spectrometry (LIBS).
 
LA-ICP-MS SPECTROMETRY
Laser Ablation System Model UP-213A/F (New Wave Research) with ICP-MS 7500A (Agilent)
The inductively coupled plasma-mass (LA-ICP-MS) spectrometer is used to qualitative and quantitative compositional analysis by measuring a mass concentration of a substance, especially on light elements such as Be (beryllium) contained in a sapphire treated by a new heating process. This analytical method is capable of rapidly measuring a wide range of elements from helium to uranium, in very minute amounts (i.e., parts par million [ppm] to parts per billion [ppb] levels).

In this technique, a minute amount of the sample is vaporized by a high-energy laser beam, and the vaporized material is ionized into a plasma by a power generator. The ions are directed into a mass analyzer, where they are separated according to their mass-to-charge ratio and then sent to a detector. A spectrum is then generated that represents the masses of components of a sample.
This instrument can be used to detect trace levels of Be (i.e. 0.1 ppm) in corundum to detect diffusion treatment. It can also provide data that can be used to create chemical fingerprint diagrams for geographic origin determination, and can be also used for the identification of mother of pearl by analysing trace elements included in it.
 
In March 2003 GAAJ-ZENHOKYO was the first lab to introduce this instrument, which is today a commonly used system of analysis in the gemmological field.
 
LASER TOMOGRAPHY
Laser tomography system to observe crystal structure
GAAJ-ZENHOKYO first introduced this instrument to the field of gemstone examination in 1984 and continues to conduct research with this analytical device.
Its function is to detect very fine structure and defects inside a gemstone using a scattering image or a fluorescent image by scanning a narrowed laser beam (488nm argon laser).
This analytical technique is internationally regarded as an effective technique to reveal the formation origin or heating history of ruby and sapphire as well as the origin of quartz. The advanced analytical report known as the “Gemstone Analysis Report” is issued bearing these varied details.
 
LASER INDUCED BREAKDOWN SPECTROMETRY
LIBS2000+system (Ocean Optic)
CFR200 (Big Sky Laser)
 
Laser induced breakdown spectrometry (LIBS) can detect a full range of major, minor, and trace elements simultaneously, and its low cost and easy operation have attracted the interest of several gem laboratories. It is for the effective detection of Be-diffused heat treatment in corundum. 
 
This technique is based on the principle that when an infrared laser converges on the surface of a solid sample, the temperature of the surface rapidly heats up and causes vaporization, with ablated aerosols (gaseous particles) entering into an electronically excited state. As the laser pulse diminishes, the excited electrons emit light wavelengths characteristic to the element they represent while they drop down to the lower energy level.
Although its detection limit is not as low as LA-ICP-MS, it has a high sensitivity of 1ppm level for Be.
 
The minute spot of less than 100 m in diameter is left by this analysis, which is similar to that of laser inscription that is widely performed on diamonds without disturbing a beauty of the gemstone, and the size is as small as we can barely confirm by a 10X lens.
 
 
CATHODE LUMINESCENCE EQUIPMENT
Luminoscope elm-3 (Premier American Technologies Corp
This method is the most effective means for individual recognition and identification of synthetic stones.
This instrument is used to observe luminous phenomenon of a gemstone when exposed to an electron beam, known as cathode luminescence.
Diamonds show uniform luminescence under ultraviolet light, but cathode luminescence of each diamond shows unique patterns according to the difference of luminescence intensity.

In particular, natural diamonds show distinct luminescence figures (CL figures) that reflect their growth histories. No two growth histories are the same and are thereby similar to individual human fingerprints.
GAAJ-ZENHOKYO issues a “Diamond Fingerprint” report which provides the growth history of an individual diamond and can be considered as the resume of the diamond.
 
 
RAMAN MICROPROBE SPECTROSCOPE
Laser Raman micro spectrometry system-inVia (Renishaw) 633nm and 325nm(UV) excitation laser, with liquid nitrogen cooling system.
Laser Raman micro spectrometry system-model 1000 (Renishaw) 514nm and 488nm excitation laser, with liquid nitrogen cooling system.
GAAJ-ZENHOKYO was the first laboratory to introduce the Ramanscope and has been using this analysis technique since 2000 to identify the colour origin of diamonds.
Raman scattering is used to identify a specific substance or to analyse the molecular structure of gemstones. It has become a standard technique in the study of gemstone inclusions in the gemmological field by using high resolution laser.
Raman spectroscopy is used to analyse samples in various micrometer sizes as well as localised area analysis. This method is also capable of identifying inclusions in a gemstone.
When fluorescence is detectable , as in the case of diamonds, this technique is used as a photoluminescence analysis. The photoluminescence method is currently the most effective way to detect HPHT processes in diamonds.
 
SPECTROPHOTOMETERS
The use of high precision Spectrophotometry is a standard technology used in most gemmological laboratories today. The GAAJ-ZENHOKYO laboratory is equipped with various types of instruments ranging from UV to visible light machines as well as near infrared and infrared light instruments. The type of spectrophotometry used is selected according to the gemstone variety or the examination required.
 
• UV-visible region
UV-2450 and UV-2400 pc-vis recording spectrophotometer
Measurement at room temperature (SHIMADZU).
The measuring range of the instrument is between 200 and 900nm, and is used to analyse the spectrum unique to the gemstone in the UV visible light range.
This instrument is used to identify the colour origin of a coloured diamonds, colour treatments of pearls or pearl oysters (eg: black lipped pearls), as well as the determination of ruby, emerald or alexandrite from synthetic or natural origins.
 
• Near-infrared region
UV-3100pc-vis recording spectrophotometer
Measurement at room temperature (SHIMADZU).
The measuring range of the instrument is between 200 and 2700nm and spans from the UV to visible and near-infrared light region.
As this instrument is capable of detecting water and organic substances that cannot be seen in visible light region, it is able to distinguish organic gemstones and gemstones containing hydroxyl group or H2O from their ?simulants. It is also very effective in detecting stones that have been injected with foreign materials eg: jadeite that has been injected with resin.
 
• Infrared region
IR Prestige-21 at room temperature (SHIMADZU)
FTIR-8300 at room temperature (SHIMADZU)
AIM-8800 Automatic Infrared Microscope (SHIMADZU)
The measuring range varies from 1250 to 25000nm, within the normal intermediate-infrared light region as well as the near-infrared and infrared light region. These instruments are primarly used to detect resin injected treatments as well as to determine diamond types as well as being able to identify quartz varieties. They are also effective in identifying gemstones that have similar RI values.
 
X-RAY FLUORESCENCE ANALYSIS DEVICE
JSX-3200 energy-dispersive X-ray fluorescence analysis (JEOL)
JSX-3600 energy-dispersive X-ray fluorescence analysis (JEOL)
When a substance has been exposed to X-ray radiation, an element that is contained within the substance emits a secondary X-ray radiation that is unique to the element. By examining this secondary X-ray (fluorescent X-ray), the type of element as well as its quantity composing the substance can be detected. As a gemstone is composed of particular chemical elements, this compositional analysis is a highly effective method to identify gemstone species, natural or synthetic origins as well as ? pearl oyster. It is also effective to detect natural or synthetic origins through the process of analysing trace elements. Standard analytical devices can detect elements whose atomic number is 11 or over such as sodium, whereas these advanced instruments are capable of analysing elements whose atomic number is six or cover such as carbon. The analysis is, of course, non-destructive.
 
X-RAY RADIOGRAPHY DEVICE
X-ray transparency equipment type-C60 (Softex)
This analytical device is used to observe the different x-ray transparency of different substances.
This is effective to identify synthetic diamonds and injection treatment. It is also effective in ascertaining whether a pearl is nucleated or non-nucleated.
 

DIFFERENTIAL INTEFERENCE MICROSCOPE
Differential interference microscope ECLIPSE-600 (Nikon).
This instrument is used to observe microscopic areas which reveal a slight variation in thickness and RI as well as fine surface structure. In addition slight irregularities show up as brightly coloured interference patterns which can be observed as a 3D image. This analysis is useful in identifying possible coatings or films on the surface of the gemstone. It can also ascertain if filling materials were used as well as identify KM treatments.
 
DIAMONDVIEW TM
The DiamondViewTM developed by DTC uses very high-energy ultra-short-wave UV radiation to introduce fluorescence in diamond and reveal growth patterns that facilitate the separation of natural from synthetic stones. Its principle is very similar to CL technique, that is, DiamondViewTM employs shorter wave ultraviolet light instead of electron beam in CL technique. The DiamondView has better operationality but CL method can provide clearer image of fluorescence image.