We are pleased to announce the unveiling of our new Gemological Laboratory facilities!
As a sapphire jewelry company, we believe that the most effective way for us to
inspect and guarantee our sapphires is to have our own on-site gemological laboratory.
At the Natural Sapphire Company, we have always been staffed
with trained gemologists who inspect our gems. We have recently taken a major leap
forward with the incorporation of a suite of advanced gemological equipment and
trained staff, dedicated full time to the examination, identification and evaluation
of our gems. Having this advanced equipment on-site, along with knowledgeable and
experienced technicians provides us with many benefits. It allows us to save our
customers hundreds of dollars in certificate costs. It reduces our expenses by allowing
us to choose to get independent verification from other labs only when we already
know what the results will be. It also provides us with an additional layer of verification
that our trusted suppliers are correct in their descriptions of what we buy from
them.
Our laboratory is able to perform all manner of tests on gems of any type, and as
a sapphire jewelry company we specialize in tests related to natural sapphires (and
their sister-gems, natural rubies). We pride ourselves on the detection of heat
treatment, fillers, synthetics, and diffusion in sapphires and rubies and also on
our skill in the art of determining the country of origin of
our gems.
The investment in our gemological laboratory is a testament to our desire to bring
the best to our customers. We are the only private jewelry company in the United
States that has an advanced laboratory on premises, and we welcome clients visiting
us in person to take an in-house tour of our new gemological facility.
Laboratory
The most important gemological-mineralogical criteria used for the characterization
of gemstones are:
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• Inclusion features – These include cavity fillings, growth features,
and other characteristics within the gem that are large enough to be seen with a
microscope. If more information is needed than the microscope provides, some advanced
equipment can be used to report on inclusion
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• Chemical fingerprinting – This is a breakdown of the major, minor,
and trace elements that make up the gem.
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• Spectral fingerprinting – This is a detailed analysis of the way different
types of light (particularly ultraviolet, visible, and near-infrared range light)
interact with the stone. It can be used to determine the type of gem, its origin,
and any treatments it has undergone.
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In order to analyze the characterization of gemstones - to determine the distinctive
characteristics of natural, synthetic, and treated gem materials - advanced gemstone
testing requires a variety of powerful analytical tools. These modern research instruments
are used in the world’s leading gem testing laboratories and have been installed
at the Natural Sapphire Company’s laboratory facilities to provide our customers
with the most advanced testing options.
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Many
gem materials and treatments can be identified using classical gemological equipment
such as the binocular microscope, the spectroscope, and the refractometer, but detecting
today’s increasingly sophisticated synthetic and treated gemstones with these
tools is nearly impossible. New processes for creating synthetic gems and for artificially
altering natural ones, require updated methods and tools for detection. Today, we
turn to more advanced scientific instrumentation to help us properly identify where
a gem originated and what has been done to it.
When analyzing a gem, it is extremely important that it is not damaged by the analysis.
Gems are carefully cut to achieve their beauty and are often very valuable; damaging
these precious objects can significantly reduce their value and great care must
be taken when examining them. Most techniques and instruments for analyzing gems
do so by analyzing how different types of light interact with the gemstones. Essentially,
the instruments shine different kinds of light on the gem. Sensitive detectors quantify
exactly how the light has passed through, reflected off of, been absorbed by, or
otherwise interacted with the gem. Different aspects of the gem’s physical
and chemical composition are revealed through these processes. When we combine all
of the test results we are able to create a detailed description of the stone and
its past.
All gemological methods must damage the gem as little as possible. Using light waves
to gather information causes no damage to the gemstone and is considered the best
technique. Occasionally, a customer would like to know other information about a
gem that cannot be gathered from light testing methods. In these instances, techniques
have been developed to gather the required information in the least damaging way
possible. For example, to test the hardness of a gemstone, the technician must make
a very small scratch in an inconspicuous place. Happily, hardness is no longer a
critical component of gem analysis like it was in the past, and the scratch test
is now almost never necessary.
In order to collect all the information a customer may want though, there are a
few other tests that need to cause a very tiny amount of damage to an inconspicuous
area of a gem. For example, to test if a gem has been artificially colored through
a Beryllium diffusion process, a laser beam is used to create a tiny pinprick-sized
nick (less than 200 microns in size) on an unimportant part of the surface of the
stone. The material in that nick is converted by the laser into a tiny glowing cloud
that detectors analyze in order to detect the artificial colorant.
Fourier Transform Infrared Spectrometer (FTIR)
A Fourier Transform Infrared (FTIR) spectrometer records the intensity of infrared
light wavelengths that pass through, are absorbed by, or are reflected off when
infrared light is directed at a sample. Sometimes the light is redirected by a system
of mirrors to pass by the sample many times before being analyzed. The spectrum
(a pattern representing the interaction of light with the sample) that results from
this process represents the molecular absorption and transmission of the elements
within the stone, creating a molecular “fingerprint” of the sample.
Like a fingerprint, this infrared spectrum is unique to each type of material. This
makes infrared spectroscopy useful for several types of analysis.
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FTIR spectrometry is widely used in both research and forensic analysis in the gemological
field, enabling identification of foreign substances (such as oils or resins in
the case of a fracture-filled emerald) in treated gem materials. A number of synthetic
gems can be distinguished from their natural counterparts by differences in their
infrared spectra. Type I and Type II diamonds can also be recognized.
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The Natural Sapphire Company’s laboratory uses our FTIR spectrometer for the
following advanced gemstone testing:
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• Detecting gems that have undergone heat treatment to alter their appearance
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• Distinguishing between synthetic and natural gems
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• Analyzing clarity enhancements of specific gems such as oils or resins in
a fracture-filled emerald, or polymer impregnation in jadeite jade
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Energy Dispersive X-Ray Fluorescence Spectrometer (EDXRF)
The energy-dispersive X-ray fluorescence (EDXRF) system is used to determine a gem’s
chemical composition. X-ray fluorescence (XRF) is the emission of characteristic
"secondary" (or fluorescent) X-rays from a material that has been exposed
to incoming high-energy X-rays. An X-ray beam illuminates and heats the sample,
causing the material to emit specific X-rays that are characteristic of the major
and minor chemical elements in the gem.
In general, EDXRF is widely used for elemental analysis and chemical analysis, particularly
in the investigation of metals, glass, ceramics and building materials, and for
research in geochemistry, forensic science and archaeology.
the Natural Sapphire Company’s laboratory uses our EDXRF spectrometer for
the following advanced gemstone testing:
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• Distinguishing between synthetic and natural gems
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• Analyzing trace elements to identify the geographical origin of gems
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• Detecting transition metal elements, which are responsible for the
color of many gems, as well as detecting other elements that are evidence of certain
treatment processes
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Ultraviolet-Visible-Near Infrared Spectrometer (UV-Vis-NIR)
An Ultraviolet-Visible-Near Infrared spectrometer analyzes light in the ultra violent,
visible, and near infrared regions of the electromagnetic spectrum. Light from these
ranges are directed at the gem and the results are recorded.
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Absorption in the visible range directly affects the color of materials. Light from
this region of the electromagnetic spectrum causes molecules to undergo certain
electronic transitions and processes where light passing through the gem moves the
electrons in the gem’s atoms. This determines the color of the gem by causing
the material to absorb certain colors and reflect, transmit, and emit others.
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The UV-Vis-NIR spectrometer is used to collect absorption and reflectance spectra
from gems to help determine geographic origin and detect treatments. The Natural
Sapphire Company’s laboratory uses our UV-VIS-NIR spectrometer for the following
advanced gemstone testing:
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• Analyzing trace elements to identify the geographical origin of gems
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• Detecting gems that have undergone heat treatment to alter their appearance
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Laser Induced Breakdown Spectrometer (LIBS)
Laser Induced Breakdown Spectrometers (LIBS) use a high energy laser pulse to gather
information. The laser is focused to form plasma which atomizes and heats up samples.
Plasma is a state of matter, like solid, liquid and gas, but is even hotter than
the gas state. In a plasma, material has been superheated to temperatures so high
that bonds between the atoms in the material break down, releasing ions and electrons.
With this laser-created plasma, LIBS can analyze any matter regardless of its physical
state, be it solid, liquid or gas, and is limited in its analytical ability only
by the power of the laser and by the sensitivity and wavelength range of the spectrograph
and detector used.
In analyzing gems, the spectrometer operates by focusing the laser onto an inconspicuous
area on the surface of the specimen. When the laser is discharged it ablates (vaporizes)
a very small amount of material (in the range of nanograms and picograms) which
generates a tiny high temperature plasma plume. At the high temperatures found when
the plasma is first created, the ablated material breaks down into excited ionic
and atomic particles. Within a very short period of time, the plasma then expands
at supersonic velocities and cools. At this point the characteristic atomic emission
lines of the elements can be observed with the spectrometer. The spectrometer allows
for measurement of the trace-element chemical composition of gem materials, including
importantly, Beryllium.

Beryllium Treatment
In 2001, stones treated by a new process entered the market. The color of these
stones resulted from diffusing the element beryllium into them from the outside
in a process akin to dyeing cloth. This technique allowed one to manufacture valuable-looking
yellow, padparadscha, and orange sapphires from low-value starting material. Later,
it was shown that beryllium diffusion could also lighten overly dark blue sapphires.
Suddenly, for sapphire treatment companies, the search for the “Holy Grail”
was over; this process had the potential to dramatically rewrite the book on corundum
rarity by allowing treaters to create certain valuable colors in sapphires in an
almost undetectable manner. However, LIBS now allows us to detect this treatment
in order to determine whether a stone’s color is a product of nature or a
product of human intervention.
Services
The Natural Sapphire Company is pleased to offer our laboratory services to the
public. Please see our Services page to learn more about gemological testing and
appraisal services. If you would like a tour of our laboratory we do offer special
tour visits. Please contact us for more information.