Real Gemstones Or Fakes? How To Tell The Difference


Real Gemstones Or Fakes? How To Tell The Difference

"How do you know if a gemstone is real or fake?"

Below, we dive into  five key principles to help you become an educated buyer - ready to enter the world of rare colored precious gems, prepared and confident.

Although the above question is tricky to answer, there is one piece of advice you should always keep in mind:

If you don’t know your stones, at least know your seller.

And a good place to start ‘testing’ your seller is by asking these 4 questions:

  1. Could I see other similar stones?
  2. Is this stone natural or synthetic?
  3. If the previous answer was ‘natural’, ask: Has this stone been treated?
  4. Can ​I get an independent gemological lab certificate?

To give you some more insights as to what you should look for in the answers given to you, I have summed up 5 things for you to keep in mind when buying loose colored gemstones or a gemstone piece:

1. Get To Know The Names Of The Best Quality Gemstones

You may be surprised to know that there are other fine quality gemstones besides the three most well-known coloured stones: emerald, ruby and blue sapphire. 

For example, there is this exquisite grass-green tsavorite garnet which can easily beat the emerald in quality… And some other fine quality green gems are: the demantoid garnet, green beryl, lagoon or neon mint tourmaline, peridot and sphene.

The same applies to the red hue: can you name other high-quality varieties besides the ruby? (Like red spinel, reddish tourmaline and garnet...). And do you know any yellow gemstones, blue ones or even neon pink ones?

It pays off to first do some research online or buy a book on colored gems so you’ll be aware of the high-quality gemstones available. Your gemstone dealer or jeweler will thank you for it as you’ll be able to articulate what you want and the colors you like.

2. Learn The Difference Between Natural, Synthetic, Man-made and Fake Gems

It’s helpful to know these distinctions before you enter a gem dealer’s office or jewelry store. So let’s dive into some gemological definitions of each.

  • A natural gem is any gemstone that is entirely the product of nature. It’s unaltered by humans in any way, except for ordinary cutting and polishing. 
  • A synthetic gem is the same as a natural gem (in terms of physical, chemical and optical properties), EXCEPT that it has been made by humans. 

For instance, synthetic diamonds, rubies and blue sapphires are just a few common synthetic gems that exist. These synthetic stones you could call the 'fakes'. But there is actually nothing wrong with them as long as you’re aware of it and you paid a lower price.

  • Man-made gems are the same as synthetic gems - with a subtle yet important difference - they don’t have a natural counterpart.

Synthetic gems always have a natural counterpart, such as synthetic diamond, synthetic ruby, etc. while man-made gems are basically invented by humans but don’t exist as such in nature. Examples are the man-made diamond simulants YAG and GGG. 

Fine-quality, natural gemstones are the rarest and will be the most valuable of all of the above. It’s good to know about these distinctions though as it’ll make you ask the right questions and it’ll make you appreciate a highly valued natural gemstone even more. 

If you’d like to discover the perfect stone for you, you can also take my quiz and find out!  


3. Be Aware Of Gemstone Treatments

Synthetics, fakes, natural gemstones and now you mention gemstone treatments?... Great. So, what is a treated gemstone?

  • A treated gem is when a  gemstone has been altered by humans, in addition to  the ordinary cutting and polishing.
Treatments are very common in gemstones, including diamonds.  Most consumers though are not aware of them or they automatically assume the word treatment has a negative connotation. This is not always deserved for all treatments! 
The reason that treatments exist is simple: without gemstone treatments, there wouldn’t be enough quality-colored gemstone stones in nature to satisfy the jewelry demand in the world... Yep, you heard that right.

When you take for instance, blue sapphires and rubies. The demand for these gorgeous stones is far greater than what Mother Nature can supply. Or in good jewelry-quality at least… For that reason, 95% of natural rubies and blue sapphires have been heat-treated. Just to turn a lower quality stone into a higher quality one and make it suitable for jewelry. 

Heat treatment is a fully acceptable treatment in the gem market by the way. Likewise, most emeralds are oiled and fracture-filled (which treatments are not always acceptable but let’s save that for another blogpost…). Then there exist some other treatments, like irradiation (accepted for certain stones but less acceptable for others) and lattice diffusion (which most reputable gem dealers don’t accept). 

And don’t forget that also diamonds can be subjected to certain treatments, such as laser-drilling and fracture-filling!

However, many treatments get lumped together under the blanket term “enhanced” which makes it difficult to understand what specific type of treatment has been carried out and also whether it would be acceptable to a reputable gemstone dealer or not. 

Always try to get a specific answer from your gemstone vendor. It's important to know specifics about a treated stone and to ask your gemstone vendor about his/her policy on treatments.

In general, a treated stone should be less expensive than a similar, untreated gemstone and on top of that, some treatments are simply not acceptable to a good gem dealer. Ask your vendor about his/her policy!

4. Learn To Judge A Colored Gemstone’s Appearance (Roughly)

The most important feature that determines beauty and value of colored gemstones is: color. And judging color is done best by comparing similar colored gemstones that are placed together. That’s because our memory of color is short.  


Eva using a loupe to inspect the hue, saturation and tone of a colour stone.

Only when you see a few colored stones of the same type, color, size and shape next to each other, will you be able to pick the best stone from the lot.

What should you look for?

Colour grading consists of 3 elements: namely the grading of

(1) the stone’s hue,
(2) saturation and
(3) tone.

Hue means that you need to try and assess the stone’s main primary and secondary color... So a stone can be orangey-red or greenish-blue for instance.

Saturation is about judging the vividness of the color or the lack of color. Generally, the more vivid a color, the more valuable a stone will be. The redder a ruby or the bluer a blue sapphire, the better the stone is. Try to avoid hints of brown or grey in the color. We don’t like those.

Tone relates to the presence of blackness in a stone. Generally, a medium tone is good for many colored gemstones out there.

On top of  colour (by far the most important judgement-call you need to make), you can look at the clarity and transparency of a colored stone, the symmetry of the cut, its brilliance (i.e. if it sparkles a lot): all indications of a higher quality gem.

All this means you need to go to several jewelry stores, gem dealers or fairs to see several gemstones and train your eye! 

You can read more tips for judging the beauty of a colored stone in my blog post here.

Indeed you'll have lots of things to check. I know. A good quality colored gem requires some work. But I promise you’ll love the process!

5. Protect Yourself With A Gemstone Certificate

Today it’s a safe practice to ask for a lab certificate on any ruby, sapphire or emerald purchase over $1000.

An example of a GIA Identification report.

For stones of lesser value I wouldn’t advise to get a certificate. 
Besides those three famous stones, you can also ask for a certificate for some other stones, such as high-quality spinels, certain tourmalines or garnets - provided they have a significant value. Your gemstone vendor might charge a fee to facilitate this. It’ll be worth it. Not only for your own peace of mind but also if you want to sell the stone later on.

Ensure that the certificate:

  1. comes from an international reputable gem lab, like Gübelin, GRS, GIA, SSEF, AIGS and NEVER from a small, local lab
  1. states the name of the stone, that the stone is natural and its treatment, if any
  1. states the origin of the stone (but this is only for those gem aficionados  who are keen to know this as you need to pay extra for origin determination)

For instance, origins like Burma (today’s Myanmar) or Ceylon (today’s Sri Lanka) are desired origins for gem collectors and those stones will be sold at a premium. 

I personally don’t care about origin so much as long as I have a very beautiful gemstone! So, I’d leave the famous origins (and their extreme premium prices) for the connoisseurs who almost value the provenance more than the actual beauty of a gem.

To sum up all the points we went through:
after you've done some research on your own, feel free to ask the vendor about their gemstone policy, especially on gemstone treatments! Don't be intimidated and try to get a specific answer. If that's not possible, go elsewhere. An educated consumer should be welcomed by a reputable gem dealer. 

Did you recently purchase a gemstone? What questions did you ask before finalizing your purchase? Were you happy with the answers? Let me know, I'd love to hear!

And if you'd like personal guidance from a certified gemologist, gem dealer and jewelry designer, book a complimentary private consultation with me to have all of your questions answered while exploring my collection of fine gems and jewelry pieces! In person or via a video consult ✨