Rainbows of Color Created by the Most Unique Gemstone, Opals!

loose opals for custom jewelry design from Nikki Lorenz Designs

Well, the month of October is almost over and I would be remiss in my resident gem-nerd duties if I didn’t write about opals.  So pull up a chair and get cozy...here we go!

Opal is one of the birthstones for October.  (The other is pink tourmaline, but that is a whole ‘nother post.)

Most people know what an opal looks like, but do you know why it looks that way?  (Here comes the geeky science part.)  Opal is formed when rainwater passes through silica-rich rock and trickles down to meet a temporarily high water table.  As the water table steadily evaporates little microscopic balls of silica form and line up like good little soldiers, all neat and orderly-like.  Light hits these little spheres of silica and is bent to show its spectral colors.  The resulting show you have the pleasure of watching is called play-of-color.  It’s like a rainbow; when sunlight hits water vapor in the air and bends light to cause the spectral show we see in the sky but in a convenient portable size!

There are only a few places in the world where you can find the right type of rocks, the perfect amount of rainfall at the perfect time, and a water table that fluctuates in just the right way.  Most people know opals come from Australia but did you know they are also found in Brazil, Mexico, and Ethiopia?  Mexico has mostly fire opals.  Brazil has precious opals and fire opals.  Ethiopia has translucent opals whose play-of-color seems to float inside the gem.  

There are two main groups of opal, precious and common opal.  Common opal doesn’t have play-of-color, it’s poor little silica soldiers just couldn’t get their shit together and get organized, so no show.  Precious opal’s silica beads are all organized nicely like the good little soldiers they are.

Opals are also organized according to their body color.  Body color is the color you see behind the portable light show you’re watching.  There are black opals and white opals which are pretty straightforward.  Water opals and crystal opals tend to be more translucent.  Fire opals are amazing with their bold, beautiful colors and last, but not least, there are boulder opals.  Boulder opal is one of my favorite types.  

I say “a little more durable,” but bear in mind that is relative.  All opal is fairly delicate and needs to be worn with care, especially if your opal is in a ring.  (Don’t even get me started on the very polite tongue-lashing I gave a customer one time when she told me she’d been wearing her ridiculously large, drool-worthy opal while gardening!)  Also, opal contains a lot of water (remember that whole water-trickling-through-rock thing?) and can actually dry out over time and get kind of hazy.

In the end, no matter what kind of opal you have they are still incredibly unique gems that each has an individual personality that can’t be repeated, so wear with care but enjoy it like the unique thing it is.

I’d love to help you bring a gorgeous opal into your life!  Let's chat about designing your custom opal jewelry!

Talk to you soon,


P.S.  Most of my work is one of a kind so while you’re in my shop make sure you sign up for my email list!  I’ll let you know when new work is available!