Black Opals in 18K Gold

These gorgeous  perfectly matched solid black opal earrings illustrate the global reach of the gem trade. We acquired the stones a few years back from an Aussie opal cutter in Lightning Ridge, Australia, then sent them to Nepal last year. Each leg of their journey was about 8,000 miles, so these opals have traveled the circumference of the earth, flashing their their electric blue play-of-color to the far corners, west to east, east to west, then west to east again.

Our intrepid world traveling friend and gemologist Michael invited us to send him gems to take along on his annual trek to Nepal. Michael produces Shangri-La Sterling with stones for which he has a steady supply. You can see the entire Shangri-La collection at this website, http://www.shangrilasterling.com/index.php–give us a call for the password.

We thought it would be great to make up some unique one-of-a-kind pieces with stones that are more unusual, so we sent several gems that you don’t often see, like the simmering fire engine red Burma Spinel, the vivid grass green Chrome Diopside and the velvety violet-blue Spinel shown below. Just to make things really interesting, we included gems that show unusual optical phenomena, like Cat’s Eye Chrysoberyl, Cat’s Eye Spectrolite, Star Sapphire, and of course, Opal. We think the results are outstanding and well worth the six months wait–here are a few samples.

A really nice thing about our one-of-a-kind and beautifully intricate hand made Shangri-La pieces is their outstanding value–for example, the beautiful Chrome Diopside ring is only $175, while the stunning Tanzanite ring in 18K gold is $1495. Hurry down to the shop to see the entire new collection of rings, pendants and earrings–these choice pieces won’t last.

.47 ct Red Spinel in Silver

.88 ct. Chrome Diopside in Silver

1.30 ct. Blue-Violet Spinel in Silver

1.67 ct Mexican Fire Opal in 18K Gold

.50 ct Tanzanite in 18K Gold.

3.57 ct. Black Star Sapphire

Flash Patterns in Lightning Ridge Opal, I-14753

What makes opal such a fascinating gemstone? When asked what opal looks like, most people would probably first think of the typical white base opal with little sprinkles and twinkles of color.

White Opal with Pinfire/Chaff Pattern Play of Color

This unique display of color is a phenomenon correctly known as play of color, not fire as it is sometimes referred to. Any opal with play of color is commonly called precious opal .

The truly amazing thing about precious opal is the rich variety of patterns and color groupings we see.  Within the gem community, we classify these patterns with descriptive terms, the three basic groups of which are Pinfire, Flash, and Harlequin. Many precious opals display several patterns.

The most common pattern is called pinfire, also referred to as chaff, twinkle, and straw, often seen in white opal and in opal fossils, such as this opalized clam shell.

Pinfire in Opalized Clam Fossil

Other types of precious opal, such as black opal and boulder opal, display their play of color against a dark background. Since the appearance is much more dramatic, these types of opal are more sought after.

Lightning Ridge Black Opal with Chaff and Pinfire Pattern

Pinfire type patterns are often rather static, meaning their overall appearance is much the same from any direction. Other pattern types may change dramatically depending on the angle of view– this can add a dynamic element to the color presentation, but can also detract if the directionality is not optimal. It’s not unusual for opals to show more than one pattern.

Boulder Opal Pair with Pinfire and Broad Flash, I-8992

Flash patterns display larger areas of play-of-color that often shift or change color with movement. Variations: Broad Flash, Rolling Flash, Exploding Flash, Ribbon, Rainbow.

Broad Flash

Rolling Flash moves across the stone as the viewing angle changes or the stone “rolls.”

Rolling Flash, View 1

Rolling Flash, Mid rotation

Rolling Flash, View 3- rotated 180 degrees

Sometimes, rolling flash will present itself as a streak or “lightning bolt”

Lightning Bolt

Ribbon pattern in Brazilan Opal

Harlequin patterns have large, distinct, and usually rectangular patches of play-of-color with edges that touch each other. Variations: Checkerboard, Flag, Fish Scale, Flagstone. The colors of the pattern may change with viewing angle.

Harlequin Drop, Lightning Ridge Black

Harlequin Drop, View 2

Harlequin pattern in 7.75 ct. Lightning Ridge Crystal Opal

And finally, we occasionally find gems that speak to us in pictures or symbols. As a kayak fisherman, I have seen storm clouds and rain moving across the Sea of Cortez at morning sunrise– just as I see in this wonderful picture opal!

Baja Sunrise in Boulder Opal

Generally, the more dramatic the pattern, the more valuable. The more coverage of the face up appearance, the better.  The more colors, the better, especially if the colors include a full spectrum, or lots of reds and oranges. And of course, the more brilliant the colors, the more rare and valuable the stone will be. The best opals have full coverage with interesting patterns of many colors, brilliantly displayed. For a full description of how opals are graded, visit our opal grading page, and view more fine opals in our Gallery of Gems.

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