Saitama prefecture is very famous geological district in Japan. This district was found the 199 mineral species. Several minerals were able to cut. Calcite was transparent and used the optical material. Jadeite was idiomorphic crystal. This size was approximately 0.5mm. Spinel was attractive blue color by Zn. Yellowish green Garnet analyzed it as Andradite. Such Andradite is called Demantoide. These minerals were founded at Chichibu area in Saitama. Chichibu area is known before 200 years ago. The fibrous serpentine which named asbestos called “Kakanfu(火浣布)” by Gennai Hiraga（1728～1780）. Chichibu area is one of the Japan Geoparks. The Global Geoparks will be selected from the Japan Geoparks. The Global Geoparks initiative was launched by United Nations Educational, Scientific and Cultural Organization (UNESCO).

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Trapiche is the Spanish word for a wheel used to grind sugar cane. The types of crystals, which have a structure radiating in 6 directions, are called trapiche because of their resemblance to the shape of a wheel. Especially trapiche emeralds are the most famous. Diamonds’ “Trapiche”, which are thin and have a pattern radiating in 3 directions, are sold in mineral shows or jewelry shows, and have become popular lately. It is well known that diamonds have a cubic system but emeralds have a hexagonal system. The difference can vary their surfaces or structures, and makes us doubt whether we can call these diamonds “Trapiche” the same as trapiche emeralds. As we conducted research on them with a magnifying inspection and some analysis, we're going to give a presentation about them. Also we will report rare diamonds we observed recently.

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In December 2012, six CVD synthetics larger than one carat were submitted to the Tokyo branch of the Central Gem Laboratory for diamond grading. These were the largest undisclosed samples of CVD synthetic diamond ever submitted gem laboratories. The six round brilliants, ranging from 1.001 to 1.119 ct. All had a color grade of Light Yellowish Grey, and their strong grayish hue made color estimation using “Cape” series master stones difficult. Four of the samples had a clarity grade of VS1, while the other two were VS2. Four samples had cut grades of Excellent, and two were Very Good. It was found that these gem-quality CVD synthetic diamonds are difficult to distinguish from natural diamonds using only standard identification techniques and procedure, but they were effectively identified using PL and UV luminescence techniques. The 736 nm lines in the PL spectra and the layered growth striations observed in DiamondView images are the two most important characteristics for identification of these CVD synthetic diamonds.

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When beryllium diffusion corundum became apparent, the presence of beryllium in corundum indicated it was beryllium diffusion corundum. But in recent studies, trace amounts of beryllium are sometimes detected in untreated natural corundum.
In this study, we have analyzed by LA-ICP-MS more than 1000 pcs of corundum which submitted to CGL in 2013. We report not only a present situation of beryllium diffusion corundum but also untreated beryllium-contained corundum.

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In the Republic of the Union of Myanmar located in the central area is Mogok, and to the north Nam-Ya. These two areas out of just a handful of sources in the entire world are where some of the world's finest untreated rubies are produced. Mori's long history in Myanmar along with geological evidence can access and collect information of; Mogok mine reports, production of rubies and the expected status of production in the field and possible mining areas in the future. With professionals in the field and expertise in identification; we are aware of the present and future state of distribution, the all important ORIGIN (mine and country) and other matters such as Mozambique rubies being put into the mix. In addition, Mori's Myanmar (in subsidiary FC12) produces 20 ~ 30pc every day, cut and polished gemstones directly from the mining area.
Those rubies are put on a high-powered microscope and any inclusions are photographed and recorded into a database. Mori's has collected over 10 years of ruby inclusion photos. This data is used for; showing our customers the uniqueness and beauty of their rare treasure, for identification of that particular ruby in the future, and the information is sometimes shared with geological experts to further ruby studies. Although Mori`s Ruby is well known as ruby specialists we are not scientist. We need accurate information from gemologist in order to have complete confidence that we are providing our valued customers with the precious treasure that they expect they are spending the hard earned money on.

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There are some treatments for valuable color of blue sapphire such as dyeing, heating, diffusion. Among of them, heat treatment with development of techniques and effort has been performed for deriving beautiful blue color of sapphire until nowadays. This tendency is caused by recognition that corundum is commonly heated as enhancement.
Improvement of the blue color by heating starts from the 19th century, it was started in earnest in the 20th century[1]. It needed oxidizing-reducing conditions by gas diffusion. The process modifies color of too dark or pale blue sapphire or removes unnecessary inclusions for clarity enhancement[2]. In addition, it needs proper treatment technique which is suited for different geographic origin due to color, impurities, inclusions, etc. Therefore, it is required to various conditions and skills with experience of heat treatment for valuable color of sapphire.
Many Koreans have a lot of interesting in treatment techniques of gemstone for creating added value. One of Korea company has tried to enhance color of blue sapphire by applying with HPHT(high pressure and high temperature) apparatus. The apparatus was designed for synthetic diamond by Russia. It took many attempts with thousands of conditions to finally get to valuable blue color from pale blue color. The president of the company explained that we did not only supplementation of the HPHT apparatus but developed mold was designated for sapphire treatment.
We need to get more information about treatment process and conditions in detail. It is difficult to distinguish the new treated sapphire from general heated sapphire by magnification inspection. But it was observed distinct feature with infrared spectroscopic analysis.
It is noticeable news that valuable blue colored sapphire can be produced by unique process in Korea. Therefore, we need to study to get more information of the newly treated sapphire by HPHT apparatus.
1. T. Ted, The heat treatment of ruby and sapphire, Gemlab Inc., USA (1992) p.xi-xvi.
2. K. Nassau, Gemstone enhancement: History, Science and State of the Art-2Rev.ed, Butterworth Heinemann (1994) p.122-131.
3. T. Ted, The heat treatment of ruby and sapphire, Gemlab Inc., USA (1992) p.141-218.

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There is no doubt of recent popularity of red and blue spinel. Thus, we see some synthetic stone in the market and gem testing lab too. Also, some reports are published that there come some heated stone. This time, we reviewed traditional gemmological features of natural, heated and synthetic spinel of blue and red. Also we examined the photoluminescence and raman spectrascopy of them.
With these examinations, it is found that with synthetic spinel neverthless flame fusion or flux synthesis, show different spectra of photoluminescence. Also, the measuments are often impossible with strong fluorescence, there are some diffrence in raman spectra too.
With heated spinel, the raman peaks are changed as reported in previous research. After heating, FWHM become less and raman peak become weak.
The measurement of photoluminescence and raman require only one surface open. Thus they can be used in case we can not get enough clue such as seeing the proper inclusion on mounted stones.
Reference:
[1] A.-K. Malsy et al, “Orangey-red to orangey-pink gem spinels from a new deposit at Lang Chap, Vietnam” Journal of gemmology, 2012 Volume 33, Nos 1-4
[2] O'Donoghue, M. (2008) Gems Robert Hale Ltd., United Kingdom

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Recently, we find facet cut peridot from pallasitic in the market. This time, we could have a chance to test 23pcs samples of pallasitic peridot from Admire pallasite and some other pallasitic peridot, we conducted all possible gemmological examination and compare them with ordinal (earth origin) peridot from various locality. In addition to traditional gemmological examination, we checked magnetism, UV-Vis absorption, FT-IR, chemical composition with EDXRF, raman spectroscopy.
Some differences from ordinal peridot were found. The most interesting features are inclusions. In pallasitic peridot, 1) unique needle inclusion, 2) liquid inclusion with high iron content inside, 3) pallasite inclusion which is host rock of pallasitic peridot 4) strong cleavages were found. In the sample with high pallasite inclusion, strong magnetism is also detected. Also, when we compare the relationship between R.I and S.G., there are tendency that S.G. is higher than ordinary peridot. With EDXRF, it was seen that Ni content is lower in pallasitic peridot, (except Sri Lankan fayalite type peridot (iron rich olivine).
In the comparison with other pallasitic peridot, no eminent difference was detected. Originally these pallasitic peridot were born as a collision of small planets in asteroid belt between Mars and Jupiter. Because the origin of these pallasitic peridot are same, it is implied that there were no difference between them.
Also, though pallasite peridot is found in the matrix of Ni – Fe meteorites, its Ni content is lower than ordinal peridot. This is because ordinal earth origin peridot is diffused with Ni during the mantle convention. On the other hand, pallasitic peridot was originated the furious collision of asteroids and these peridot was not affected of mantle convention even though the Ni and Fe was given from the core of collapsed asteroids.
From these research there found some differences in gemmological features between pallasitic peridot and ordinal peridot. These differences can be used for the clue of gemmological identification of them.

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Mechano-luminescence has been observed successfully from ruby and Cr doped spinel crystals during grinding, cutting and polishing processes. Bright visible light, red colored, luminescence can be observed from ruby (Cr doped Al2O3) and Cr doped spinel (MgAl2O4) crystals. Luminescence spectra agree with those of photoluminescence from Cr3+ ions in ruby and spinel crystals, respectively. Peak wavelength and peak intensity of mechano-luminescence varies with diamond discs. X-ray excited luminescence has also been observed successfully from Mn doped spinel and Mn doped forsterite crystals ruby. Green colored luminescence is observed from Mn doped spinel crystals with X-ray excitation. Red colored luminescence is also observed from Mn doped forsterite crystals with X-ray excitation. These luminescences are expected to be used in X-ray imaging application. Various luminescences from ruby, spinel and forsterite crystals will be reported in detail.

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In 2012, we reported and described about characteristics of Amazonite occur from Sør Rondane Mountains, Antarctica. We collect Amazonite samples occur from other countries and continents, and compare with the difference of trace elements. These samples contain trace elements as follows, iron and lead; they are regarded as the origin of blue color, rubidium, strontium and barium; it seems that has no relation for body color, and found the difference between these samples.
In this study, we performed preparation of thin sections for all samples, and quantitative analysis and area analysis using by EPMA are carried out.
Under observation of thin sections, there are some different characteristics, in distribution and regularity of internal structure, such as; some one has lamellar restricted by lineation. Most of them have lamellar likely to Vein or lens structure. Bands width of lamellar are different in each samples, it seems to be depend on chemical composition of melt at the time to create these feldspars, especially content of albite component. Some samples contain quartz inclusion.
Color density is different thin sections from rough stones or faceted stones.
Result of quantitative analysis show that amazonite crystals consist two type of feldspar; chemical composition of base crystal are equal to pure orthoclase, and composition of lamellar are made from pure albite, contain small amount of anorthite component. Content of trace elements are not reached to the detection limit at some analyzed points.
Area analysis are carried out to solve whether the concentration of trace elements are present or not.
The results of area analysis indicate that distribution of trace elements is almost homogeneous, and small amount of concentration are observed.
We compare this study with last year study, and consider the easy way to estimate the origin of amazonite.

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In the Bible a number of gemstones are referred. They are most often described as symbols of rarity, beauty, preciousness, and sanctity. In the book of Exodus the Breastplate adorned with 12 gemstones is stated to be made to give the High priest dignity and honor. The design, size and colors of the Breastplate and the names of gemstones and their order of arrangement are described. However, different versions of the Bible state some different names of stones. For example, the Geneva Bible in the 16th century, the Authorized Version of 1611, and the New International Version of 1973 list ruby, sardius, and ruby as the first stone respectively. The same is true among the Japanese translations: the Bible compiled in early 20th century, the one in 1955, and the Common Bible in 1987. Regarding the names of precious stones, some ancient names are not currently used, and others designated different gems in the ancient days.
Dr. G. F. Kunz and other authors have written treatises on this subject. Now, tracing the history of the translations of the Japanese Bible as well as the English Bible, gemstones on the Breastplate in the book of Exodus, and the stones of the foundations of the city wall of the New Jerusalem in the book of Revelation will be considered.

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Optical spectrometry is used to differentiate various jewels. In pearls, reflection spectrometry is a common differentiation method and is generally done using an integrating sphere. Determination of the presence/absence of coloring in black lip pearls and golden pearls is typical examples of such differentiation. However, some of gold pearls have characteristics that make it difficult to determine the presence/absence of coloring by reflection spectrometry. Such pearls tend to have strong interference colors, which are considered to influence the optical spectrum.
As we previously presented at a conference of the Gemmological Society of Japan, pearls have two types of interference color – transmission interference colors and reflection interference colors. Reflection interference colors are less influenced by the body color and exhibit the same patterns regardless of the color, assuming the same thickness of the crystal layer. Pearls with the same reflection interference color pattern show a common peak at a certain wavelength in spectrometry.
To differentiate the presence/absence of coloring, spectrometry is used to determine whether the body color of a pearl is derived from pigments or dyes by determining the wavelengths at which light is absorbed by the pearl. As mentioned above, if reflection interference colors, which are less influenced by the body color, appear on the reflectance spectrum, this needs to be considered in differentiation.
In this presentation, the interpretation of the reflectance spectrum and the effects of reflection interference colors of a pearl are discussed again from the following two viewpoints characteristic to pearls: “cause interference” and “are spherical.” Using plane and spherical objects that either cause interference or do not cause interference, how coloring by a dye appears on the reflection spectrometry pattern was compared. Also, new spectrometry methods that are not influenced by interference colors are discussed.

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When white light is applied from above at an angle of 45˚to a glass plate coated with pearl essence mixed with a resin, the light is divided into reflection interference light and transmission interference light, just like when this is done to a thin plate of the pearl layer of a seashell, allowing the observation of complementary colors for each light. Pearl essence is made by coating titanium on mica.
On the other hand, when a pearl with a strong “Teri” value is brought close to a diffused light source in a dark room, a concentric stripe pattern of reflection interference colors, which changes depending on an incidence angle, is observed on the light source side hemisphere and a concentric stripe pattern of their complementary colors is observed on the other hemisphere. However, on an imitation pearl made by coating pearl essence on a nucleus, although complementary colors can be observed on both hemispheres, clear stripe patterns cannot be observed.
Causes for a difference in color pattern that occurs on an imitation pearl when the pearl is brought close to a diffused light source are discussed from the aspects of structure, crystal axis, etc.

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We reported at the 1990 conference of the Gemmological Society of Japan that some of akoya pearls had a reddish violet nacreous layer which had specific absorbances at 370 nm and 500 nm in reflection spectrometry. Subsequently, we reported on GEMMOLOGY (August 2004), a journal of the Gemological Association of All Japan, that the same phenomenon was also observed in some of south sea cultured pearls. This time we have confirmed the same phenomenon in some of black-lip pearls.
It was estimated that this phenomenon was derived from a pigment of the prismatic layer of the outer shell layer, porphyryns as components were involved with the phenomenon, and some kind of secretion abnormality in outer epithelial cells that constitute a pearl sack is involved. The pigment was also confirmed by spectrofluorometry and a fluorescent test with ultraviolet light, and a fluorescent test could be used as simple differentiation methods.

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