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What Are Precious Stones and Gems?

I love to share my experiences and passion for the things I love. Collecting rare gemstones is one of my many interests.

The five cardinal gems of antiquity. Clockwise from top: Sapphire, Ruby, Emerald, Amethyst, Diamond.

The five cardinal gems of antiquity. Clockwise from top: Sapphire, Ruby, Emerald, Amethyst, Diamond.

What Are the Big Four?

When most people think of precious gems or stones, they usually think of diamonds, emeralds, sapphires, and rubies. These gemstones are commonly referred to in the jewelry industry as "The Big Four."

Other gemstones that many consider precious are alexandrite, topaz, opal, or tanzanite.

What makes these gemstones precious versus semi-precious gemstones or just plain old rocks?

Common Misconseptions About Precious Gems

There are a number of common misconceptions about precious gems or gemstones, especially the Big Four.


One of the most common misconceptions about Diamonds, Rubies, Sapphires, and Emeralds is that they are the rarest gemstones in the world.

All gemstones are rare to some degree. Whether it be Tanzanite from Africa or Rubies from Sri Lanka.

The special circumstances that are required to create a gemstone, pressures, heat, combinations of unique minerals, all come together to form a gem or gemstone.

When we look however, at how rare one gemstone is compared to another, there are many gemstones that are much rarer than the gemstones that are known as the "Big Four"; Rubies, Emeralds, Diamonds, and Sapphires.

For example, Red Beryl is much rarer than any of the so-called precious gemstones commanding a hefty price of nearly $10,000.00 per Carat.


Many believe that the "Big Four" are the most valuable and expensive gemstones in the world. There are many examples of gemstones that are much more valuable than any of the "Big Four" gemstones.

High-quality Jadeite can exceed the price per carat of the most costly diamonds with a hefty price of nearly $3,000,000.00 per carat.

Factors Affecting the Value of Gemstones

People often refer to the "Four C's" when referring to the value of a diamond. These same characteristics can apply to many other gemstones as well.

The "Four C's" are:

  • Cut
  • Clarity
  • Carat Size
  • Color
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The color is also a factor in the value of a gemstone. In the case of sapphires for example, a specific color of red commands a higher price than does many of the other colors of sapphire. The specific color of red sapphire is called a Ruby.


Clarity refers to the flaws or inclusions that are in the gemstone. It can also refer to any external imperfections that the gemstone may have.

Clarity can have a tremendous effect on the value of a gemstone. Finding a "perfect" natural gemstone in certain types of gems such as Emerald can be almost impossible, thereby increasing their value incredibly.

Some gemstones, however, are very commonly "eye clean" such as Aquamarine, and are expected to appear nearly perfect in appearance if they are gemstone quality.

Carat Weight

An enormous factor affecting a gemstone's value is the size of the gemstone. Many gemstones are very rare in large sizes and command substantially higher prices the larger the stone is.


The way a gemstone is cut can greatly affect the way it looks when it is finished. Each type of gemstone has specific properties that must be considered when the gemstone is cut.

Poorly cut gemstones are considerably less valuable.


The term "natural gemstone" is used to describe a gemstone that has come from the Earth. Even though the gemstone is labeled "natural" it may have had a man-made treatment to help enhance its beauty. Treatments are a standard for some gemstones like emerald, while others are almost never treated.

Rarity and Demand

Rarity in combination with demand is the biggest factor in determining a gemstone's value. This is one of the reasons that larger gemstones can command a much higher price than smaller gemstones.

On the other hand, a gemstone could be extremely rare but if there is no demand for it the price may be considerably lower than more common gemstones.

Common Gemstone Treatments




Changes purple Amythist to yellow, orange or gold



Change color to violet or blue

Pink Topaz


Change color to pink



Improve clarity and color



Improve clarity and color



Intensify Color



Deepens color and turns more blue



Lighten dark shades



Creates bright neon colors

Blue Zircon


Alter color

Colorless Zircon


Alter color



Improve color



Changes color from orange to pinkish



Hides imperfections and enhances colors



Heal / Hide Fractures



Improve color



Turn Topaz blue



Intensify color



Intensify color



Remove inclusions



Lighten Color



Lighten Color



Lighten Color



Protect and enhance color

Black Onyx



So What Is a Precious Gemstone?

Technically there really is no such thing as precious or semi-precious gemstones.

The American Gem Trade Association (AGTA) has added the following language to their Code of Ethics: "Members should avoid the use of the term 'semi-precious' in describing gemstones."

In addition to the code of ethics statement by the AGTA, the US Federal Trade Commission periodically considers banning the use of the terms to reduce consumer confusion.

This content is accurate and true to the best of the author’s knowledge and is not meant to substitute for formal and individualized advice from a qualified professional.

Questions & Answers

Question: How can I find out the value of an 83 CT sapphire?

Answer: If you would like to know the value of your sapphire you should take it to a professional to have it appraised. Carat weight, color, and cut are not the only factors that determine a gemstones value. It would be impossible to determine a value based on a description alone.

© 2013 Marty Andersen


newusedcarssacram from Sacramento, CA, U.S.A on February 27, 2013:

Thanks for the detailed information. It is not easy to recognize a precious stone by general people.

Neelum Waqar from Pakistan on February 26, 2013:

I love gemstones! I would like to know

more about other gemstones apart

from the usual diamonds and sapphires.

Very interesting hub.

idigwebsites from United States on February 26, 2013:

I love gemstones! I would like to know more about other gemstones apart from the usual diamonds and sapphires. Very interesting hub. Voted up and useful/interesting/awesome/beautiful. :)

talfonso from Tampa Bay, FL on February 25, 2013:

Wow - I was floored when you noted that alexandrite is one of the precious stones and gems. It's my birthstone besides pearl. Good thing I paid for a class ring with that stone for less!

Thanks for writing this Hub!

Marty Andersen (author) from Salina, Utah on February 24, 2013:

Paraiba Tourmaline is a fabulous gemstone. Like so many gemstones it is much more rare than diamond in fact they are among the rarest gemstones on earth. Similar gemstones have been found in Mozambique and Nigeria. Paraiba Tourmaline can sell for over $5,000 per carat with gemstones over 3 carats going for over $10,000 per carat.

Mazlan A from Malaysia on February 24, 2013:

Congrats on HOTD. Another gemstone that was not listed, but considered rare and expensive is Paraiba Tourmaline. It has a beautiful neon blue color and is relatively a new gemstone. It was discovered in the late 80's in Paraiba, Brazil.

Minbani on February 24, 2013:

My favourite is Moonstone. I have been collecting it for a few years now and still find the 'running of the colours' soothing yet inspiring. -a weird combination. The other thing I find so useful as a jewelry piece, is that I can wear it with anything in my wardrobe as the colours adapt and compliment my outfit.

Be warned though that there is definitely some very inferior and very low quality 'moonstone' being sold on the Internet.

A quality stone is quite heavy and has the colours of a tropical aquarium running through it when you turn the stone around. And never buy a stone that has the back covered so that you can't see the flaws.

A well written informative article so thank you and congratulations on getting Hub of the day ~ Well done :-)

Marilyn Alexander from Vancouver, Canada on February 24, 2013:

Very interesting hub on gemstones. I believe I love the amethyst best of all.

Katee Shew from Canada on February 24, 2013:

I always enjoy your Hubs, they have so much information! Congratulations getting Hub of the day!

Vinaya Ghimire from Nepal on February 24, 2013:

My father knows a lot about gems, (Sadly I don't know anything). He usually associate the stone with astrology.

Congrats on Hub of the Day!

Leah Lefler from Western New York on February 24, 2013:

I love gemstones - they are so pretty. I didn't realize they heated, bleached, and even dyed certain stones to improve on color and appearance. Congratulations on HOTD!

Thelma Alberts from Germany on February 24, 2013:

Congratulation on the HOTD! This is a very informative hub and well written, too. I love these precious stones. Thanks for sharing.

Andrew Stewart from England on February 24, 2013:

Very interesting introduction and overview of the world of precious gems. I find their creation deep within the Earth very interesting and also value we put on them. Keep up the good work, voted up and Thank you.

Proud Foot on February 24, 2013:

As a child I was a huge lover of gemstones. That disappeared. But this wonderful hub has unlocked the love again. Thank you for sharing and congrats on Hub of the Day!

Ishwaryaa Dhandapani from Chennai, India on February 24, 2013:

A well-written & detailed hub! You explained this topic very clearly. I am an aspiring jewelry-designer and have a guidebook about 130 gemstones of the world. Congrats on the Hub of the Day award! Well-done!

Thanks for SHARING. Useful & Interesting. Voted up & pinned

Mary Craig from New York on February 19, 2013:

You would think being a woman I would know about gemstones, but I didn't. This hub was very informative and I love the pictures, especially the Super Swiss Topaz! Amazing.

Voted up, useful, and very interesting.

wabash annie from Colorado Front Range on February 19, 2013:

Thanks for writing about gemstones ... they are absolutely beautiful!

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