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An Almost Magical Gem For People Who Can’t Pick Just One Favorite Color

Yeah, so that name is long and cumbersome, but so is the name of this gem: tourmaline. It gets a little more complicated; since tourmaline comes in every color, sometimes all in the same stone, each color and most color-combs of tourmaline have their own name, like schorl (black tourmaline) or rubellites (red tourmaline). The colors added to the legend of tourmaline, but it was the seemingly mystical properties of the stone that propelled it to great heights.

Tourmaline gems. Photo created by and uploaded to wikicommons by Didier Descouns.

But before I get to the magic, let’s talk a little bit more about the color. Tourmaline is an aluminum boron silicate mineral, and it’s particularly sensitive to even small changes in composition, and boy-o-boy can that get complicated. Unlike diamonds, which are pure carbon, tourmaline can include many, many different elements, and chemical formulas for these stones can get as wild and wacky as my last name (hint: my last name is Polish and unwieldy).

The changes in chemical composition can vary even within a stone, which is why bicolor and multicolor tourmalines are so common. In my opinion, the best bicolor tourmalines look like watermelons ““ they sort of resemble candies, though, and with tourmaline ringing in at a whopping 7-7.5 on the Mohs scale, this could make them dangerous for teeth.

Unpolished bicolor tourmaline crystal with watermelon coloring. Photo from Rob Lavinksy/irocks.com, found on wikicommons.

But even if the gem only has one color, the color could change based on cut and light source. Depending on how the stone is cut, looking at the stone from different angles can make the stone seem deeper or paler in color. As for light source, well, colors can change in artificial and natural light: in fact, the change in color is what keeps red tourmalines from being considered rubellites. If the stone is red in all light, it’s a rubellite, but if it looks pink in some lights, it’s called a shocking (shocking!!) pink tourmaline.

But the color spectrum isn’t where all the magic lies: tourmaline can be made to have an electrical charge. I used passive voice in order to postpone the reveal of the mechanics behind this truly wild property of the stones, but here it goes.

The first way to make your tourmaline electric is to heat it up. This is called “pyroelectricity.” When tourmaline is heated, it can attract small bits of stuff, like straw or ash. Now, the electrical charge will dissipate with time, so if you wanted to keep using your tourmaline to draw straw towards you, you’d have to keep heating it. Oh, and as a fun aside for the biologists/naturalists in the house: Carl Linnaeus, the guy we know and love for his work on taxonomy, was also one of the brains behind figuring out how pyroelectricity works.

But there’s more: the second way to make your tourmaline electric is to apply pressure and deform it. This is called “piezoelectricity,” which sadly has nothing to do with actual pie. Curses! Oh Greeks and your “piezo” meaning “stress” and not “so much pie I give it a silly name by adding zo.” Anyway, the theory behind piezoelectricity was propelled by the Curie brothers, Jacques and Pierre (yes, the Pierre Curie that married Marie Sklodowska and worked on radioactivity with her).

So not only does tourmaline come in every color, sometimes all at once, but it can also attract ash, and accumulate all sorts of electrical charge. I don’t know about you, but I can totally imagine a cackling witch hoarding tourmaline in her knapsack with eye of newt and hair of dog. This is one fantastic/fantastical crystal.

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