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Investigating the presence of metals on precious stones in the jewelry making process

Investigating the presence of metals on precious stones in the jewelry making process

 

Introduction

The ability of X-XRF in jewelry applications is well illustrated in this article.

In order to study metallization on precious stones, many methods have been used to identify the properties.

This paper shows how ϻXRF provides relevant information about the chemical composition of these materials. In this research, high-resolution X-ray micro analyzer made by UNISANTIS Company was used to perform µ-XRF studies.

 

Background of device application

Gemstones, which are part of a piece of jewelry, are usually classified as chips based on the analysis of fine metal particles (micron-sized). These metal particles are found in areas of rock that have been cut and mounted.

 

Used Tools

The measurement on the above sample was performed using X-ray micro analyzer model XMF-104 made by UNISANTIS company. This device is equipped with a 50 watt molybdenum tube and a high-resolution compact Si-PIN detector and two-stage Peltier cooled.

 

The EDXRF spectrum obtained from this analysis are shown in Figure 1.

 

The dimensions of the device are significantly reduced and the detector no longer needs liquid nitrogen to cool down.

 

The XMF-104 uses a Polycapillary focusing lens that produces a very small focused X-ray. The usual size of the focal point at the lens output varies between 50 and 250 microns.

 

Discussion

The EDXRF microanalysis spectrum obtained from the emerald sample can be seen in Figure 1. This spectrum clearly shows the presence of gold and copper in the sample. Quantitative analysis of chemical compounds is determined using approximation of initial parameters. The results show the presence of 58% gold and 42% copper. These results also show that the metal particles on the rock are an alloy of gold and copper.

 

Conclusion

The present study demonstrates the simplicity of operation and capability of the XMF-104 X-ray micro analyzer manufactured by UNISANTIS in research on precious stones and jewelry.

 

Such a study was made possible by the EDXRF spectrum obtained from the XMF 104 micro analyzer. This device is equipped with a low power tube. In this device, the primary X-ray emitted from the low-power tube is paralleled using a Komakhov polycapillary lens.

 

Other benefits

UNISANTIS XMF-104 devices are:

  • No need for gas
  • No need for an external water cooler system for the X-ray tube
  • Small effect range
  • Low power tube

Investigating the presence of metals on precious stones in the jewelry making process

 

Introduction

The ability of X-XRF in jewelry applications is well illustrated in this article.

In order to study metallization on precious stones, many methods have been used to identify the properties.

This paper shows how ϻXRF provides relevant information about the chemical composition of these materials. In this research, high-resolution X-ray micro analyzer made by UNISANTIS Company was used to perform µ-XRF studies.

 

Background of device application

Gemstones, which are part of a piece of jewelry, are usually classified as chips based on the analysis of fine metal particles (micron-sized). These metal particles are found in areas of rock that have been cut and mounted.

 

Used Tools

The measurement on the above sample was performed using X-ray micro analyzer model XMF-104 made by UNISANTIS company. This device is equipped with a 50 watt molybdenum tube and a high-resolution compact Si-PIN detector and two-stage Peltier cooled.

 

The EDXRF spectrum obtained from this analysis are shown in Figure 1.

 

The dimensions of the device are significantly reduced and the detector no longer needs liquid nitrogen to cool down.

 

The XMF-104 uses a Polycapillary focusing lens that produces a very small focused X-ray. The usual size of the focal point at the lens output varies between 50 and 250 microns.

 

Discussion

The EDXRF microanalysis spectrum obtained from the emerald sample can be seen in Figure 1. This spectrum clearly shows the presence of gold and copper in the sample. Quantitative analysis of chemical compounds is determined using approximation of initial parameters. The results show the presence of 58% gold and 42% copper. These results also show that the metal particles on the rock are an alloy of gold and copper.

 

Conclusion

The present study demonstrates the simplicity of operation and capability of the XMF-104 X-ray micro analyzer manufactured by UNISANTIS in research on precious stones and jewelry.

 

Such a study was made possible by the EDXRF spectrum obtained from the XMF 104 micro analyzer. This device is equipped with a low power tube. In this device, the primary X-ray emitted from the low-power tube is paralleled using a Komakhov polycapillary lens.

 

Other benefits

UNISANTIS XMF-104 devices are:

  • No need for gas
  • No need for an external water cooler system for the X-ray tube
  • Small effect range
  • Low power tube

Training

Control System Abzar Novin co., is ready for training with the analysis instruments. These courses are held quarterly and are about XRD, XRF and OES and include operator training, education and technical training, software and hardware training for these instruments.

Participants in these course are familiar with the principles of X-ray spectrometer, they will receive training to work with the devices, analysis of data and software & hardware training to repair the device. These courses are held in the factory.

 

 

Examine ancient coins with the help of Micro XRF

Silver has been an important currency metal for much of history, with the value of a coin usually proportional to the amount of silver within the metal alloy. However, even though strict standards existed during different periods and in different places, the amount of silver present in coins may vary significantly. For example, reducing the amount of silver included when making the coins, or debasement, was one possibility to “make” more money. This was common practice in times of war allowing soldiers to be paid and supplies purchased, but has also been attributed to inflation, trade, and a lack of raw materials needed to produce the coins. Therefore, knowing the precise composition of a coin allows them to be dated, and offers interesting insights into the political situation at the time of manufacture.

Analysis of modern alloys is all but routine. However, historic alloys such as silver coins present several analytical challenges. Commonly composed of materials or mixtures uncommon in modern alloys, ancient alloys typically require additional validation of the quantification routine by using appropriate certified reference materials. In addition, the modification or degradation of the coins during the passage of time means the sample itself represents its own challenge, such as the formation of patinas covering the true alloy hampering an accurate compositional characterization.

Painting analysis

The “Virgin of the Rocks” is a famous artwork by Leonardo da Vinci. The painting exists in two versions. One of them is displayed in the National Gallery in London. It owes its current radiance to an elaborate restoration in which the latest examination methods including image processing technology were used. An M6 JETSTREAM spatially resolving micro X-ray fluorescence spectrometer from Bruker Nano GmbH Berlin played a decisive role in this. It enabled investigations of the smallest paint particles and delved into the depth of the paint layers. Two USB cameras from IDS Imaging Development Systems GmbH provided the necessary optical information of the sample surface and ensured the exact positioning of the spectrometer over the measuring area.

The “Virgin of the Rocks” is a famous work by Leonardo da Vinci and shows the Virgin Mary with the Christ Child, the boy St. John and the angel Uriel in a rock cave. The painting is one of three panels, all from an elaborate and partially sculpted altarpiece made for the Church of San Francesco Grande in Milan. One of actually two versions is displayed in the National Gallery in London. The painting owes its current radiance to an elaborate restoration in which the latest examination methods including image processing technology were used. An M6 JETSTREAM spatially resolving micro X-ray fluorescence spectrometer from Bruker Nano GmbH Berlin played a decisive role in this. It enabled investigations of the smallest paint particles and delved into the depth of the paint layers. Two USB cameras from IDS Imaging Development Systems GmbH provided the necessary optical information of the sample surface and ensured the exact positioning of the spectrometer over the measuring area.

Even great masterpieces can suffer from aging. Color changes such as yellowing or small amounts of damage cloud the brilliance of the colors and must be repaired from time to time. Extreme caution is required with a picture like the “Virgin of the Rocks”. The restorer must study painting techniques and know exactly the chemical composition pf the colors that were used in order not to destroy the uniqueness of the painting. After several years of research into the feasibility and safety of a possible conservation treatment, da Vinci’s London “Virgin of the Rocks” was finally cleaned and restored. The treatment was carried out primarily for aesthetic reasons since the picture had become increasingly darker and less “recognizable” due to the strong degradation of an oil and mastic varnish applied in 1949.

The analytical examinations of the painting were carried out not only before starting the treatment but also during the cleaning. This allowed valuable information to be gathered on the condition of the surface layers as well as the layer structure and the materials used. The examination of the elemental composition simultaneously provides information about the authenticity of the colors.

For example, great artists may have bought some paints “on the open market”, but mixed the typical colors themselves. Thus the colors used can give an indication of the authenticity of a painting. If, on the other hand, the painter is not known exactly or if several contemporary artists worked on the same painting, the type of brushstrokes and the choice of colors can reveal which part of the picture belongs to whom. Thus the second version of the “Virgin of the Rocks” was probably begun by Leonardo da Vinci and continued by his pupil Ambrogio de Predis. The knowledge about Leonardo da Vinci’s painting practice could be greatly expanded and also documented through the analyses.