Standard gemological methods of diagnostics are often not applicable to gems framed into jewelry (for example, the frame may not allow placing a gem into a refractometer to measure its refractive index). Raman analysis helps determine mineral species of any framed gems or even installed in massive jewelry. Raman spectroscopy doesn’t require mechanical contact of the instrument and a test sample. This property allows using Raman spectroscopy in studies of museum articles and jewelry having historical value.
Raman spectroscopy is a highly efficient tool for rapid analysis of gemstones and minerals. Analysis of their surface and inclusions reveals a number of facts, i.e. the origin and genotype and whether the mineral has been treated. Now, this kind of diagnostics can be carried out within several seconds by means of the benchtop EnSpectr R532 analyzer, portable Raman microscope RamMics M532 or handheld RaPort analyzer.
EnSpectr Raman and micro-Raman instruments implement a variety of Raman spectroscopy advantages as applied to gemology and mineralogy, being inalienable diagnostic tools especially when rapid results are required. The instruments by far reduce the time of analysis and significantly increase the accuracy of gemstone identification including mounted gems. EnSpectr supplies compact handheld Raman and micro-Raman devices that enable lab as well as field analysis.
Raman spectrometry allows analysis of the majority of gemstones and minerals though, of course, the method has its own restrictions.
Some gems i.e. cryptocrystalline minerals, like larimar or opal, may induce strong photoluminescence that can be partly cured with a special CCD shutter (used with EnSpectr devices). Alternatively, laser power may be diminished, measurement time increased, or low-wavenumber analysis applied.
Attention should be paid to thermally unstable gemstones and minerals, for instance, ruby silver, as they could melt under strong laser emission. In such cases, measurement time and laser power should be set carefully.
EnSpectr R532 is a benchtop Raman analyzer with superior sensitivity, combining the advantages of a portable probe system with performance of a highly specified laboratory instrument. The instrument covers the spectral range of 100-4000 cm-1 and is capable of measuring Stokes and anti-Stokes algorithms. EnSpectr R532 can be equipped with a special CCD shutter that cuts luminescence of difficult-to-analyze gemstones and minerals. Put the device on the sample stage or use special attachments for jewels for better sample positioning.
Advantages:
- Nondestructive identification of gems & materials
- Authentication and anti-counterfeiting of gemstones
- Lightweight and portable for in-situ laboratories
RaPort is a handheld Raman instrument for rapid in-situ identification of gemstones and minerals based on the benchtop EnSpectr R532 model. The RaPort analyzer has been installed at the Center of Gemmology, Japan (research), the Customs of the Russian Federation (authentication and anti-counterfeiting of gemstones), the Gemmological Center of the Moscow State University (expert laboratory: identification and evaluation of gemstones), etc.
Advantages:
- High-quality results outside lab: identification and verification of gemstones and semiprecious gemstones, identification of isomorphs and subspecies.
- Discovering the essence: direct measurement of jewels regardless of Luminescent spectrum of sapphire Luminescent spectrum of beryl setting or jewelry type. The wide spectral range of 100- 4500 cm-1 is complemented with a shutter covering red-yellow photoluminescence.
- Rapid analysis: time per measurement < 3 seconds.
Superb delicacy and sensitivity: even with laser power of 12 mW and less (which is crucial in case of temperature unstable gems) RaPort enables rapid acquisition of high-quality spectra of gemstones and minerals. RaPortensures nondestructive high-level protection of gemstones. - Instant data at your fingertips: use the instrument with your smartphone/tablet on Android OS or a PC. Data transmission via Bluetooth, long battery life.
Raman microscope RamMics M532 integrates the opportunities of the Raman Analyzer EnSpectr R532 Scientific Edition and Olympus BX-43 microscope adapted both for transmission and reflection measurements. The 3 Mp CCD camera allows focusing on each tiny internal gas-liquid inclusion and cracks providing information about the origin of the mineral, its deposit, and type of treatment.
Advantages:
- Analysis of internal gas-liquid inclusions as well as surface inclusions
- Examination of gem feathers and fillers which enables determination of the fact and type of treatment
- Analysis of jewel gemstones in most intricate settings