Certifications of authenticity from reputed laboratories can help clear the air around this so that you can navigate the enthralling world of gemstones without deception. Keep reading to know more about the certification and authenticity of gemstones.
What is an Authentic Gemstone?
The Gemological Institute of America states that any gemstone, whether natural or lab-made, can be classified as “real” if it contains a mineral makeup identical to that which appears in nature. This means that a lab-made synthetic diamond (CVD), for example, is just as “real” as a natural one, but at the same time, it cannot be called natural. In a general sense, gemstones can be classified as follows.
1. Natural Gemstones
Natural gemstones are those that are formed organically under the Earth’s surface over millions of years, and are mined, cut, and polished for use. They are made up of specific types of mineral crystals and earthy minerals, which contribute to their structure and colour. More often than not, natural gemstones contain inclusions of other minerals, liquids, or gases. Common treatments like thermal enhancements do not change their composition or alter their structural integrity.
2. Synthetic Gemstones
Synthetic gemstones are grown in laboratories under controlled conditions. They can be called real because their mineral composition is 100% identical to that of naturally occurring gemstones. These gemstones come with inclusions that depend on the method used and the conditions under which they are grown. Common treatments like thermal enhancement or surface polishing do not change their mineral composition.
3. Simulated Gemstones
Sometimes certain crystals or glass pieces are passed off as gemstones because of their appearance – which may be similar or identical to more valuable natural gemstones. These include spinel (passed off as ruby), and cubic zirconia (passed off as diamond) – which by themselves are authentic stones, but can be considered simulants when passed off as other, more precious gemstones. This is usually done by unethical and often less-known traders in order to make a quick buck.
A gemstone is only as authentic as the trader selling it, and an ethical gemstone trader will properly disclose the physical and chemical characteristics of the gemstone, to the best of his/her knowledge. This is where a certificate of authenticity from a gemmology lab comes into play.
What is a Certificate of Authenticity?
A certificate of authenticity is a document issued to a specific gemstone that states the physical and chemical characteristics of a gemstone. These are issued by renowned laboratories and can provide you with all the essential information about the gemstone you are purchasing. The accuracy and detail that a certificate can provide, depend on the level of testing technology and expertise available at the lab.
A certificate of authenticity can be procured from ISO-certified or other international labs across India. Such certificates usually describe the mineral family of the stone, its carat weight, colour, shape and cut, dimensions, and refractive index. They may also comment on any treatments that the gemstone may have undergone.
A detailed certificate includes information about the optical behaviour of the gemstone, such as transparency and optic character, present inclusions, and even the country or region it was mined from. Detailed certificates of authenticity can be procured from internationally renowned institutions such as the International Gemological Institute (IGI) or The Gemological Institute of America (GIA). GIA and IGI certificates are internationally recognised and accepted, and provide detailed testing reports on most varieties of gemstones.
Testing with state-of-the-art technologies that offer the highest levels of accuracy can also be done by premium research labs such as Gübelin or GRS. But such testing costs thousands of dollars and is reserved only for the best quality specimens, which themselves cost a fortune.
Renowned Certification Labs
Gübelin Gem Lab
The Gübelin Gem Lab is said to be the premiere research laboratory for gemstones and jewellery in the world. It primarily serves clientele in Europe but works with an international clientele as well. It has a rich history and dedicated staff, and makes use of the best technology for testing. The costs of their reports start from ₹25,000 (CHF 250) and may go up to ₹2,50,000 (CHF 2800 +) and beyond.
Figure 1: A sample Gübelin report on a Colombian Emerald
GRS
GemResearch SwissLab AG, established in 1996, specializes in identifying and characterizing high-quality coloured gemstones from new as well as classic mining regions. They excel in colour grading and brandings, such as the famous GRS-type Pigeon's Blood rubies and Royal Blue sapphires. With labs in Hong Kong, New York, Bangkok, and Switzerland, GRS Lab provides a global expertise in gem research and testing.
Figure 2: A sample GRS report on a Tourmaline
Swiss Gemological Institute (SSEF)
The SSEF testing lab at the Swiss Gemological Institute in Europe is a new, but highly reputable and reliable gemstone testing laboratory. In a relatively short span of time, the lab has pioneered very important research testing methodologies within the diffusion identification process in sapphires.
Figure 3: A sample SSEF report on a Diamond
Gemological Institute of America (GIA)
As one of the oldest and most well-known gemstone experts in the world, the GIA has been in operation since 1931. They are a leading authority on gemstones, diamonds, and pearls, and are also one of the premier institutes of gemstone and jewellery education. GIA’s detailed gemstone testing is known for its accuracy but is usually reserved only for high-quality specimens due to the high cost involved. The cost for regular test report from GIA can start from ₹5,000 - ₹10,000, and increases with an increase in the carat weight of a stone.
Figure 4: A sample GIA report on a Diamond
International Gemological Institute (IGI)
The International Gemological Institute (IGI) is a distinguished name in the gemstone industry. It operates 20 laboratories worldwide that grade finished jewellery, natural diamonds, lab-grown diamonds, and coloured gemstones. IGI also operates 14 schools of gemmology that produce thousands of jewellery professionals annually. IGI reports on gemstones are highly accurate and reliable, and are recognized across the world.
Figure 5: A sample IGI report on a Burmese Ruby
SGL Labs
SGL Labs is a British-American diamond certification and authentication laboratory network. With 158 geo-footprints across 5 countries, including India, it is one of the fastest-growing international laboratory networks that is committed to providing convenient testing services for its clients.
Figure 6: A sample SGL report on a Diamond-studded, Gold ring
Gemmological Institute of India (GII)
The Gemmological Institute of India (GII) is a non-profit Public Charitable Trust, established in 1971. GII is one of the most trusted gemstone institutes in India with rock-solid credibility in the research and testing of gemstones and diamonds.
Figure 7: A sample GII report on a Ruby sculpture
Geological Survey of India (GSI)
The Geological Survey of India is a governmental organization and central authority when it comes to up-to-date information on the geological information of the country. GSI prepares mineralogical reports from non-destructive analysis of gemstones that detail the gemstone’s physical and optical constants along with internal inclusion patterns.
Other Local Laboratories
In addition to being one of the top exporters of cut and finished gemstones, India is a huge marketplace for gemstones as well. As such, it has local testing laboratories in most major cities. Gemstone testing from a reliable lab in India can cost from a few hundred rupees to thousands ($5 to $100).
Some reliable Indian testing labs are:
- Indian Gemmological Institute - Gem Testing Laboratory (IGI-GTL), a 40-year-old gemstone lab backed by the Indian Ministry of Commerce & Industry, is known for its accuracy. Every gemstone certified by IGI-GTL undergoes rigorous scientific tests using advanced equipment.
- Kolkata Gem Testing Laboratory (KGTL) is another recognized name that offers gemstone testing and provides detailed reports on them.
- Shri Zaveri Mahajan Zaverat & Moti Tolai Charitable Trust is popular for the certification of pearls and is a trusted authority, based out of Mumbai. Their expertise in testing and examining various types of pearls has earned them recognition both in the Indian market and abroad.
Which Certificate Should My Gemstone Have?
When it comes to gemstone testing, there are several options. Reports can cost from a few hundred rupees (~ $5) to lakhs of rupees ($2,000 +). The latter price spectrum should be explored only in the case of heirloom gemstones of the highest quality. For good to decent quality gemstones, reliable testing from labs such as IGI, GII or SGL is sufficient, and for semi-precious stones and gemstones of relatively lower value, local lab certifications are sufficient.
At Precious Earth, we place the trust and convenience of our customers above all else. All our gemstones come with certificates of authenticity that disclose all the essential details of a gemstone such as its physical and chemical characteristics, and details of treatment, if any. We also provide detailed reports from GIA, IGI, GII, or other reputed certification labs upon request - so that you can rest assured that your purchase at Precious Earth is completely genuine and authentic.
