HOW TO TELL IF A RUBY IS REAL
STEP ONE: CHECK THE RUBY'S HARDNESS
As mentioned above, real rubies are highly resistant to scratches, ranking a firm 9 on the Mohs scale of Hardness. Real rubies rank second in durability only to diamond and moissanite gems because a diamond ranks a 10 on the Mohs scale, while moissanite ranks a 9.25. This means that only a diamond (or an object with a hardness greater than 9) can scratch real rubies. This is the same for all gems on the Mohls Scale of Hardness. For example, a material such as glass (a common material in faux rubies) is a mere 5.5 on the hardness scale, so it can only scratch stones with a 5.0 hardness ranking or below.
THE RUBY SCRATCH TEST
This is how the ruby scratch test works. If you are able to scratch the surface of the ruby in question with your nails or any other sharp instrument that is not a diamond or moissanite, then you know it is a fake ruby gem. Only a gemstone with a higher hardness rating on the Mohs scale can scratch a real ruby gemstone.
THE RUB TEST:
COMMON RUBY IMITATIONS
Glass: Most fake rubies on the market consist of red-colored glass. These synthetic rubies are affordable but aren't exceptionally long-lasting. Additionally, genuine ruby stones typically have a higher refractive index than glass, meaning they sparkle and shine more than one-dimensional red glass.
Composite Rubies: These are natural rubies with red-colored glass fused into it. Mixing these two materials creates a larger, fake stone at a lower price point than real ruby gemstones.
The disadvantage of composite rubies is that these stones contain glass and, thus, are easily fractured and harmed by chemicals in housekeeping supplies.
RUBY VS. GARNET
Garnet: Real rubies are relatively more flawed with inclusions than garnets, which are usually clearer. Real rubies are also a deeper and more distinct dark red, whereas garnet stones tend to be lighter and much paler. And finally, garnet (like tourmaline) is softer than natural rubies, with a Mohs Scale rating is 6.5 to 7.5.
STEP 2: CHECK THE RUBY'S COLOR
THE RICH COLOR TEST:
The color of your ruby stone is one of the best factors to look at first. An authentic ruby gemstone has a deep, rich hue. A ruby-red color that is so vivid that it looks bright, while fake rubies often appear pale and dull, as if there is no substance.
Use the "stoplight red" as a guide, but do not expect to find a real ruby stone that is that bright. If you do, then your "natural ruby" is likely fake. However, an authentic ruby gemstone is more like a bright traffic light than a faux, dull stone.
If a gem is more of a dark shade, it is probably a garnet instead of a real ruby stone. Garnets are a common substitute for real rubies
THE GLASS TEST
Fake rubies commonly consist of glass. To determine if you have a fake ruby, compare it to similar-tinted glass. No genuine ruby will ever be identical to the color or tint of a piece of glass.
STEP 3: FEEL THE RUBY'S WEIGHT
Fake rubies are often less dense than real ones. To tell if a ruby is real, you must weigh the questionable stone and compare the weight to a similar-sized natural ruby. A faux one will be lighter in weight than a real ruby stone.
STEP 4: A REAL RUBY IS PRICEY
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 rubies will always be rarer and more valuable. If the price of ruby gem is too low, there's a good chance it is a fake ruby - or a very low-quality one.
In general, a natural ruby is very costly. In contrast, a lab-created ruby is about 20% less expensive than a natural ruby, while a synthetic ruby can be up to 90% cheaper.
In terms of size, it is tough to find a natural ruby in a larger size. However, the stones that are the real deal and come in larger carats are extremely rare & expensive. If a ruby is quite large, there is a high probability that it is a synthetic ruby.
STEP 5: INSPECT THE RUBY'S CLARITY
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 a natural ruby under a microscope in a process called spectroscopy. These flaws usually aren't visible to the naked eye.
These flaws are 'inclusions.' Natural ruby forms as a mineral deep in the earth; thus, a genuine ruby will always have flaws - sometimes a black spot, a line, or inclusions from foreign minerals.
In addition, a real ruby stone usually has consistent clarity; thus, your stone is likely not a real ruby if the clarity is not consistent throughout.
STEP 6: EXAMINE THE CUT RELATIVE TO ITS SIZE
Most real rubies over ½ carat in size are usually cut into fancy shapes, such as a pear or cushion shape. Thus, if you have a larger carat-size ruby in a round shape, it may be a false ruby.
STEP 7: NATURAL RUBIES COME WITH CERTIFICATION
By following these steps, you should have a better understanding of how to tell if a ruby is real or not. If you are ever in doubt, it is better to get a professional opinion and let an expert confirm the authenticity of your ruby. Doing so will help ensure that you buy only genuine rubies and not artificial ones. Good luck!