Ultrafast laser used to detect counterfeiting of precious gemstones
February 14, 2008, Las Cruces, NM--Raydiance Inc., developer of a compact, cost-effective and fully software-controlled ultrashort pulse (USP) laser system, is working with a leading geologist at New Mexico State University (NMSU) who has received funding for laser-induced breakdown spectroscopy (LIBS) of rock and mineral compositions, a process by which researchers are able to analyze small parts of a mineral in a way that is essentially non-destructive.
As part of this initiative, the precision and power of the Raydiance USP platform will allow researchers to differentiate fake gemstones from real gemstones, as well as uniquely identify individual gemstones with certainty, without causing damage to the stones. Until now, other lasers that have been effective at this technique have not been small, portable, precise or inexpensive enough to be practical for commercial use. They have also typically caused collateral damage to the material being examined.
Nancy McMillan, PhD, professor and academic head of the Department of Geological Sciences at NMSU and principal investigator of the gemstone project, said, "Lasers have been used in the past to determine the type, origin and quality of gemstones. However, until we saw Raydiance's technology in action, we had never seen a laser that does not cause damage to the stone, lowering its value. Looking ahead, we expect the Raydiance USP laser platform to be an invaluable tool for appraisers and insurers across the industry."
McMillan's project aims to illustrate how Raydiance lasers can detect gemstones that were treated to look like real stones, such as chemically-coated diamonds, rubies injected with leaded glass to superficially remove flaws, and sapphires that have been diffused with the element beryllium to produce a brilliant orange color. The research will also test the laser's capability to identify minerals that are being illegally sold as more expensive ones, such as synthetic forsterite sold as tanzanite.
Today, gemstone evaluation most-commonly consists of either subjective visible inspection, examining a stone's refractive index, or inspection with a microscope.
USP lasers are extremely brief light pulses of unprecedented power that, unlike continuous wave lasers, instantly vaporize any material without heat or residual damage at very precise scales, down to the micron level. Until now, most USP systems have been extremely expensive, very large and usable only by photonics experts.
Raydiance President Scott Davison said, "We are thrilled to partner with NMSU on these exciting, groundbreaking projects. As a leader in research and development, NMSU is exactly the type of research hub we look to partner with to develop innovative commercial applications that will not only disrupt the marketplace, but also foster knowledge-based job growth for the state of New Mexico."
Dr. McMillan's work is one of six research projects on the Raydiance USP laser platform currently underway at NMSU. Each multi-disciplinary team is developing novel applications based on the unique properties of Raydiance lasers to identify promising, high-growth ideas and projects that can be commercialized within New Mexico. Other projects include spectroscopic techniques for sensitive detection and identification of chemical species or microorganisms and live imaging of neural and sensory tissue for biomedical applications.