The C that Really Matters: Judging Gemstones by Color

The C that Really Matters: Judging Gemstones by Color

So they tell you that you have to judge the value of a gem by the four C’s: Carat, Clarity, Cut and Color.

Carat refers to the weight of the gem of course.  A larger gem will cost more than a smaller one, not only because of it’s sheer size but also because prices jump according to weight.  This is very obvious when you consider diamonds: one carat diamond costs more per carat than a .95 carat diamond. 

Clarity is about the inclusions in a gem. The more included the gem, the lower its value.  Each gem should be judged vis a vis other gems of its kind, because an emerald need not be as clean as a sapphire to be valuable, whereas a tanzanite should be cleaner than a sapphire (it should be loupe clean, actually).

Cut is important because if the facets are not properly angled – for example – the gem may have window and thus be less pretty. 

Color, however, should be the most important of the four C’s. It is certainly my first C.

Why? Because color is the first thing you see. Consider: someone steps into a dimly lit room wearing a top color Paraiba tourmaline ring. You will see it from several feet away. A neon color Paraiba is an eye turner. After that, you may notice the size, but even a small Paraiba will pack a punch. To know the clarity of the gem or the cutting, however, you have to put it close to your eye, or even loupe it. It’s not therefore what draws you in. You want a Paraiba because of its unique and unmistakeable color. 

And not just Paraiba. Pinkish-red Jedi spinel, cobalt spinel, the German Hauyne, royal blue sapphire, Colombian emerald, all of them are show stoppers because of their color. Even softer colored gems, like a Padparadscha color sapphire, owe their beauty to their color, first and foremost.

An old school gem dealer once imparted the following piece of advice to me: If you don’t like it, don’t buy it. Simple right? Not really. The above mentioned Padparadscha sapphire is a good example. In some of the old stock photos referred to in judging the ideal color, you can see a near perfect Lotus Color mix of pink and orange, exactly right to make it seem pink, peach and orange all at the same time. 

But in real life, even expensive Padparadschas are often too pale, too pink, too orange, too brown. I would counsel against buying those. One has to like the stone, not just think it valuable. Once the current Padparadscha craze has passed, the prices on the not so pretty specimens are going to come down much faster than on the really gorgeous ones. If that happens, one owns a lemon, not a lotus.

When I go on location and am offered new and unusual stones, I have to keep this advice in mind as well. I can’t allow myself to buy a green kornerupine just because it’s a kornerupine. The really neat-looking Kornerpine are not green, they are tealbluegreenpurple. They have a bunch of colors, soft yet extremely eye-catching. Green kornerupines are very pretty but they are not as out of the ordinary pretty as the tealbluegreenpurple.

Alexandrite, like Padparadscha, is also stone that is more expensive than its color suggests it should be. Most available material on the market that has a good color change is muddy looking because it’s the silk in the stone that helps the color change along. Also the good color changers are often darker in daytime lighting. I don’t know how many times I have had a client interested in an alexandrite, only to be disappointed when they actually see it in real life.

On the bright side – literally: the finest specimens of Burma spinel – the Jedi’s – are not actually red.  And they are not actually pink. They are redpink or pinkred, and that means that some online descriptions (and sadly also the photos) can often be misleading. The color is hard to photograph, hard to describe, but it’s the color that makes it a Jedi, and gives it most of its value.

When you get to the greens, the finest specimens of grossular garnet are not tsavorite, and not mint garnets – which is a commercial distinction made for advertising purposes by the way as it’s THE SAME stone. The most beautiful grossular is where the two colors meet, the one where one can’t always decide whether or not it should be a tsav or a mint. Let your eye be the judge, not the description.

I think you get where this is going: trust your eye. Trust it, but also train it, and you’ll be able to judge color as well as the next person. Keep looking and looking and looking. If you are as obsessed as I am, you should not find that difficult.

Look in person (monitors can be deceiving, so can photography). Look In natural but diffused daylight, outdoors or by a window. The closer you are to the equator, or the cleaner your air, the less light you need. In NY for instance, our light is 10% darker or more because of pollution.  And in winter, our afternoon light is very yellow. If you are just starting out with your looking, buy a few melee gems for practice, or just gemstone beads. It’s cheaper, and also fun to play with beads.

When you use indoor light at a vendor’s office or store and are trying to decide if you want to buy the stone, make sure you know what kind of light it is: halogen, LED, fluorescent, incandescent, as well as different light temperatures and dimmable lights. Some gems, i.e. unheated sapphire and spinel, are especially affected by these lighting conditions. For traditional color changers like alexandrite and blue garnet, however, change only shows in incandescent or candle light. But the state of California, for example, no longer allows the sale of incandescent bulbs. So there goes your color change, unless you buy candles.

And in case you didn’t know: you are within your rights to ask if you can see the gem outside. That is a very standard request. You will be accompanied by a sales person who may be handling the gem at all times but outdoor light is how a gem is judged. Any, really all, indoor lighting changes the way a gem looks.

Here are some beautiful examples of amazing color currently available in our shop:

 

Trillion Cut Sugarloaf Paraiba Tourmaline
Trillion Cut Sugarloaf Paraiba Tourmaline

 

 

Cushion Cut Kornerupine
Cushion Cut Kornerupine

 

 

Oval Paraiba Tourmaline from Brazil
Oval Paraiba Tourmaline from Brazil

 

 

Cushion Cut Burma Jedi Red Spinel
Cushion Cut Burma Jedi Red Spinel

 

Cushion Cut Cobalt Spinel from Vietnam 
Cushion Cut Cobalt Spinel from Vietnam