How to Tell if a Ruby is Real


Rubies are beautiful gemstones that are popular in high-end jewelry. When searching for the perfect jewelry, there are so many imitation rubies on the market that it can be difficult to distinguish between real rubies and fake rubies. However, there are a few key things you can look for to help determine if a ruby is real or not. In this article, we will discuss some simple techniques for investigating ruby gems.



Real rubies are precious gemstones that rate a 9.0 on the Mohs scale, making them one of the world's hardest gemstones. In contrast, synthetic rubies are often substitutes such as red glass or tourmaline, and much softer gems are thus easily scratched.


The Ruby Scratch Test:


Natural rubies are highly resistant to scratches, ranking at 9 on the Mohs scale. It is second in durability only to diamond and moissanite gems. A diamond stone ranks a 10 on the Mohs scale, while a moissanite stone ranks a 9.25 . This means that only a diamond (or an object with a hardness greater than a ruby) can scratch genuine rubies. In comparison, glass is a mere 5.5 on the hardness scale.


You know it is a fake ruby if you can scratch the surface of the ruby in question with your nails or any other sharp instrument that is not a diamond or moissanite. Only a gemstone with a higher hardness rating on the Mohs scale can scratch a real ruby gemstone.


The Rub Test:


In this method, you are looking to see if your ruby leaves a color. Use the ruby in question to scratch a hard, smooth surface, such as a piece of glass. If there is a streak of red color left behind on the surface, then it is clear that you have a fake ruby on your hands.


A real ruby will never leave color in that way. The only issue with this technique is that you cannot be sure that the ruby is real if it doesn't leave a trace of color. However, you can only be certain that it is a fake ruby if it does.


Common Ruby Imitations:


  • Tourmaline: These are crystal silicates whose hardness is rated 7.0-7.5 on the Mohs scale. The pinkish-red variety of this stone is frequently marketed as other gemstones, including genuine rubies, although it is considerably softer.


  • Garnet: This is yet another variety of the same element, the mineral silicate. Garnet gems come in various hues, but the red variety of this stone is commonly passed off as ruby imitations.


Ruby vs. Garnet:

Rubies are relatively more flawed and/or inclusion-ridden than clear garnets.

Rubies are a deeper and more distinct dark red, whereas garnet stones are lighter and paler.

Garnet, like tourmaline, is softer than a natural ruby, with a Mohs Scale rating is 6.5 to 7.5.


  • Glass: The majority of the fake rubies on the market consist of red-colored glass. Those synthetic ruby stones are very affordable, but they aren't exceptionally long-lasting. Additionally, ruby stones typically have a higher refractive index than glass, meaning they sparkle and shine more.


  • Composite rubies: These are natural rubies with red-colored glass mixed in. Mixing these two materials creates a larger, fake stone at a lower price than natural ruby gemstones.


The disadvantage of composite rubies is that these stones contain glass and are easily fractured and harmed by chemicals in housekeeping supplies.




The Rich Color Test:

The color of your ruby stone is one of the best factors to look at first. A real ruby gemstone has a deep, rich hue. A ruby-red color so vivid it looks bright, while fake rubies often appear light and dull as if there is no substance within them.


Stoplight Red:

Use the "stoplight red" as a guide, but do not expect to find a real ruby jewel that is that bright. If you do, then the "natural ruby" is likely fake. However, an authentic ruby gemstone is more like a bright traffic light than a fake, dull stone.


Dark Red:

Beware, if a gem is more of a dark shade, then it is probably a garnet instead of an actual ruby. Garnet is a common substitute for actual rubies.


A Glass to Test a Glass:

Artificial rubies commonly consist of glass. To determine if you have synthetic rubies, compare them to similar-tinted glass. For example, take a piece of red glass and compare it to the counterfeit stone since no genuine ruby will ever be identical to the color or tint of glass.



Fake rubies are often less dense than real ones. To tell if a ruby is real, you must weigh it and compare the weight to a similar-sized natural ruby. Fake stones are often lighter in weight than real ones.



The best indicator that you have a real ruby gem is its rarity. Most rubies on the market are synthetic rubies made in laboratories, so genuine stones will always be rare and more valuable. If it's cheap, there's a good chance it is a fake one - or low-quality.


Natural rubies are costly. Lab-created rubies can be about 20% less expensive than natural ruby jewelry, while fake rubies can be up to 90% cheaper.


In terms of size, it is tough to find natural rubies in large sizes. However, those stones that are the real deal , and do come in bigger sizes are extremely expensive. If rubies are quite large, there is a high probability that they are fake rubies.



Buy a ten power (10x) jeweler's loupe online and inspect your "ruby" under high magnification. You will be able to detect tiny flaws on the surface of an natural ruby under a microscope in a process called spectroscopy that isn't visible to the naked eye. These are 'inclusions.' Natural gemstones form naturally as minerals deep in the earth; thus, genuine rubies always have flaws - sometimes a black spot, a line, or inclusions from foreign minerals.


In addition to this, real rubies have consistent clarity. It is not a real ruby if the stone is not consistent throughout.



Most loose gemstones that are real rubies over ½ carat in size are usually cut into fancy shapes, such as a pear or cushion shape. A round shape in a large ruby is a clear signal that it may be a synthetic stone.



This last technique is the only foolproof way to check a natural ruby's authenticity. For example, if you purchase your ruby gem from a reputable jeweler, they should provide you with official certification to prove authenticity. This documentation is usually in the form of a certificate or appraisal. If the jeweler does not offer this documentation, the gemstone in question is likely a fake one.



Rubies, arguably the most beautiful gemstones, have many imitators on the market (such as garnet). By following the steps above, you can determine if you have a natural or synthetic ruby. However, if you are still unsure, it's always best to bring your gemstone jewelry to a professional gemologist to get a definitive answer. Thanks for reading!