In the eighteenth and nineteenth centuries, natural gemstones were enjoyed by the few, upper class citizens and royalty. They were so rare and in such short supply that most people did not own gemstones. Scientists began running experiments to try to determine what the gems were made of. And, in the late 1800′s, after decades of research, scientists began to figure out the exact physical composition and structure of gems. They were then able to closely replicate the gems in a laboratory. A lab created gemstone has essentially the same chemical composition, crystal structure and physical properties as its natural counterpart. At first glance, these gemstones will look exactly like the natural versions, but a trained gemologist can distinguish between the two by examining internal characteristics. For example, with one synthetic process called flame fusion, the material produced has curved growth lines not present in natural stones. With other methods, the shapes and characteristics of the inclusions differ from natural stones which make the synthetics identifiable.
When gemstones are created in a laboratory, what’s interesting to know is that they are not really created by the scientists; rather, the scientists provide the necessary conditions to allow the crystals to grow. It’s almost as if the scientists are simulating the environment deep inside the earth where most gems are formed.
In this post, we wanted to share with you some of the history of synthetic gemstones and also highlight the important uses of various synthetic stones. The first gemstone to be synthesized in the lab was ruby. Several processes were developed in the 20th century and now dozens and dozens of gemstones can be made in a laboratory. There are low cost high volume methods that produce crystals at the rate of several carats per hour in a single furnace to high cost low volume methods that take up to a year to product a mass of crystal material.
Over the years, synthetic corundum became highly desirable since it withstands high temperature, rapid heating and cooling, high pressure and it resists chemical corrosion. During the time of World War II, under government contact, Linde Crystal and its successor Union Carbide, made small disc shaped corundum bearings for use in precision instruments. They made concave discs that were used as nose cones to protect the optical sensors on the end of the Sidewinder missiles. And in the 1960′s, they used a higher quality process to make fine quality ruby that was used in lasers. And ruby spheres were also used as the tip, or ball, in ball point pens.
Watchmakers began to use colorless sapphire crystal as the cover for watch faces. Sapphire is a hard gemstone with a Moh scale hardness rating of 9. Glass, which was previously used for watch faces, has a hardness of 5.5. So using a significantly more scratch resistant material enabled watchmakers to craft watches that could withstand daily wear and tear. And of course, this practice continues today.
Clear synthetic sapphire used for scratch resistant watch faces
Colorless synthetic sapphire is also used in supermarkets as the clear cover over the bar code scanner at the checkout stand. The scratch resistance of the material makes it a great product for this application.
Quartz (you might know it as amethyst or citrine) is another mineral that has been successfully synthesized in the laboratory. Currently there is only one method available to make quartz because the conditions needed to grow quartz are so specific and hard to achieve. Although quartz is naturally plentiful, it plays such an important role in technology that it is used in extremely high volumes. Because quartz can generate an electric current when placed under pressure and sliced quartz can vibrate in precise response to alternating current, it is used in watches, clocks, communications equipment, filters and oscillators. When you hear about a ‘quartz movement’ in a watch, it is actually the natural properties of the synthetic quartz that allows the watch to keep time so precisely.
The industrial uses of synthetic corundum (ruby, sapphire) actually generated an interest in the jewelry marketplace. As more and more people learned about the gemstones, demand increased for the natural counterparts. So the synthetics industry has actually helped the natural gemstone marketplace. Techniques for making the synthetics have improved over the 20th century and since synthetics are actually made of the same components as the natural gem, they do make wonderful, affordable substitutes, especially for the more expensive natural gems like ruby, sapphire and emerald.
MyJewelrySource does not offer any synthetic gems on our website but all of our jewelry is available with lab created stones by special order. So if you see a particular piece of gemstone jewelry on our website that you like and the price is simply more than you can or would like to spend, for example, you can always inquire as to the cost to make it with a synthetic rather than natural stones.