By: Mrs. Meenu Brijesh Vyas and Miss Gitiksha Khandelwal
The synthesis of gem crystals began in the late 1800s for industrial applications (Weldon, n.d.). During 1970, the market saw an influx of matured gem quality synthetic gemstones, with synthetic amethyst haunting the gem and jewelry market (Nassau, 1990).
With various technologies introduced for the synthesis of gemstones, the hydrothermal method has been the closest process replicating that of nature, as it effectively replicates the natural conditions under which the crystal forms. Because of this, synthetic quartz looks very similar to its the natural counterpart, making it difficult to separate.
(Image 1) Seed plate dividing the specimen in two halves. Photography by Sundeep Kumar Vijay.Gemological Science International (GSI) Jaipur recently examined a massive, high clarity, colorless spheroid shaped synthetic quartz, weighing 1588.00 grams, and measuring 16.60 x 8.00 x 8.02 cm. The specimen was inert to both long and short-wave UV radiation.
As colorless quartz crystals grown by the hydrothermal method sized up to 50 mm wide by 150 mm long are generally used in the electronic industry (Read, 1991), the specimen was initially suspected be natural, due to the size alone. Due to the size of the specimen, identifying inclusions under a microscope was challenging.
Upon orienting a fiber optic light source around the specimen, GSI visually observed a seed plate along the length dividing the specimen into two halves (Image 1). On further observation, suspended breadcrumb-like particles were observed throughout the stone.
For additional confirmation, Fourier-transform infrared (FTIR) analysis was performed using a Shimadzu IRTracer-100 FTIR spectrometer with DRS-8000A, in diffused reflectance and resolution set at 4 cm–1. The scanning ranges were 7,000–500 cm–1 (Image 2). The IR spectrum of the specimen showed peaks at 3,581, 3,298, and 3,194 cm–1, which correspond to synthetic rock crystal quartz; these are not found in natural quartz (P. Nattida N, 2015). This specimen is an interesting example of large, high-clarity synthetic quartz for use in the gem and jewelry industry.
(Image 2) Infrared spectrum of synthetic rock crystal spheroid, and a natural rock crystal from data show different absorption patterns.References
Weldon, R., (n.d.) An Introduction to Synthetic Gem Materials. Gemological Institute of America. https://www.gia.edu/gem-synthetic
Read P.G, (1991). Gemmology, 3rd edition Butterworth-Heinemann, Oxford, UK.
Nattida N, (2015). Synthetic Rock Crystal Quartz Bangle with Unusual Inclusions. Gems & Gemology, Winter 2015, pp 439-440.
Skalwold E.A, (2016). Synthetic quartz: A designer inclusion specimen, Gems & Gemology, Winter 2016, pp 425-426.
Johnson M.L. et. al, (1986). QUARTZ: A Large Crystal Ball. Gems & Gemology, Fall 1986, pp 216-217.
Nassau K., (1990). Synthetic gem materials in the 1980s, Gems & Gemology, Spring 1990, Vol. 26, pp 50-63.
About the Authors
Mrs. Meenu Brijesh Vyas is currently working as the Global Head Gemologist, Gemological Science International, Jaipur. Miss Gitiksha Khandelwal is a Junior Gemologist, Gemological Science International, Jaipur.
