We have fairly thoroughly exhausted the gemstones that Wings uses in his work with any regularity — especially those for which I have photos of the works in question. So beginning with our first Jewels and Gems post for October, and continuing until year’s end, I’m going to focus on some of the more “exotic” stones in his supply: mostly semi-precious gemstones that he has in limited quantity (often only one of each), and that he has not sued yet. For this reason, the posts from today onward will not be image-heavy; often, they will include only one photo. They will, however, introduce you to some rare jewels that you may not have had the opportunity to meet . . . and perhaps inspire you to commission an truly unique work for yourself.
I should note at the outset that, while I will periodically use the word “rare” in describing some of these stones, generally speaking, they will not carry the sort of price tag that that word usually evokes. They are “rare” in the sense of their occurrence within their broader mineral categories, or of the frequency with which they’re turned into gemstones, but they are often fairly common in many parts of the world, even if they are not (yet, at least) commonly mined for use in jewelry and art. Many of the stones we’ll be exploring in the weeks to come are members of broader mineralogical families: agate, jasper, quartz. In such cases, the specific variant may indeed be rare in terms of its actual occurrence, although the parent category is very common indeed.
We begin today with the stone pictured above, a member of the agate family, but with a twist: It’s a hybrid cabochon of polka-dot agate, containing inclusions of agate’s opaque cousin, jasper.
We’ve looked at both the agate and the jasper families here before. With regard to agate, we’ve featured the reds in this very series, as well as in a couple of pairs of earrings that Wings has created over the last year. We also introduced you to Botswana agate, around which Wings built a recent and spectacularly beautiful necklace. We’ve highlighted jasper semi-regularly, too — specifically, bloodstone and picture jasper. A couple of the pieces we’ve featured have incorporated leopard-skin jasper beads.
For purposes of today’s post, I’m going to reprise what I’ve already written about the mineralogical properties of both agate and jasper. It’s useful to understand the similarities and differences between them anyway, but it’s especially helpful in assessing the appearance and beauty of this particular stone.
As I wrote of agate earlier this year:
Agate is, essentially, one stone with seemingly infinite variations — with, predictably, a caveat or two. There are a couple of other stones that straddle the boundary between agate and some other mineral, and because of the process by which agate forms, it is also possible for entirely different minerals to take on some of its properties (i.e., becoming agatized). Don’t worry; we’ll separate all the strands of stone here.
First, what agate is: Agate is a cryptocrystalline form of silica, which is commonly known (in this context) as quartz. We’ve looked at quartz here before (and, indeed, agate itself, to a limited extent). The descriptor “cryptocrystalline” denotes the size and type of crystal structure: In the case of agate, the crystals are so small — indeed, so truly microscopic — that they appear invisible except via powerful magnification under polarized light. Thanks to this minute structure, some sources refer to this variety of quartz as microcrystalline.
. . .
Agate is nearly always a part of one specific family of quartz known as chalcedony (another mineral that we’ve explored here, too). As is usually the case, however, there are no absolutes. One of the requisite features of agate is its banding patterns (which, depending on the size of the bands relative to the size of the individual stones, may not always be visible as bands). Occasionally, minerals such as carnelian will manifest in such banding patterns; some mineralogists classify these particular variants as both carnelian and agate. Similarly, some forms of onyx, particularly sardonyx, will develop bands that permit some to classify them as part of the agate family. And, as noted above, occasionally another mineral entirely (or even another non-mineral substance, such as petrified or fossilized wood, or fossilized dinosaur bone) will be subjected to agatizing processes. As you can see in the photo [at the link], the banding is often visible even when the stone is still in rough form; you can also see how, depending on the size of the rock and the point of fracture, discrete bands may be present and yet not clearly visible as bands (i.e., you can see the wide color variation, but the lines that separate them are not clearly visible). The reverse of the collection of stones above appears immediately below [at the link]:
I’ve also covered the structural and chemical properties of jasper here before, too. As we’ll see, like agate, it’s also part of a much broader family tree: also a form of chalcedony, which is in turn a form of quartz, the earth’s second-most common mineral. Jasper is a cousin of chert, but where chert is functional, jasper tends to be frivolous. As I wrote here last year:
Jasper is a mineral in the quartz class; specifically, it’s a form of chalcedony. It is related to chert, a type of stone used by peoples ancient and not so ancient for knapping blades for use in tools and weapons.
Chert appears in plain form: an opaque substance with fairly uniform color, usually in a whitish, gray, or beige shade; it’s the sort of surface that one would tend to refer to as a “tock,” rather than a “stone.”
In its more colorful and variegated form, however, the same stone is known as “jasper,” and it comes in a dizzying array of patterns and hues. The most common shades range through the yellow-to-orange-to-red-to-brown section of the spectrum, followed by those in greenish shades of varying intensity (or lack thereof). Blues are more rare — rare in the sense that are seldom found, not especially rare in terms of monetary value. Jasper also often appears with bold decorative patterns that occur naturally in the stone: spots and splotches; agate-like bands and plumes;matrices that create the appearance of landscape “pictures”; even dendrites, tiny fossilized once-living creatures. If you have a colorful banded or plumed stone and wondering whether it’s jasper or agate, hold it up to the light: If it’s translucent, it’s agate; if opaque, it’s jasper.
Jasper that is used in gemwork is stunningly diverse. Common varieties include bloodstone, a green so deep it is sometimes nearly blue, with a brick-red matrix that often appears in a drop-like pattern, hence the name; seafoam jasper, that usually appears in white or pastel shades, with round, puffy inclusions in a variety of colors that evoke the foam upon waves; and picture jasper, which is exactly what its name implies — a stone of wildly variable colors and matrices that appear to create their own picture, usually resembling a landscape.
Earlier this year, when we covered picture jasper specifically, I clarified some aspects of the stone’s crystal structure and appearance:
[J]asper [is] a form of microcrystalline quartz. Unlike other forms of those minerals, jasper is opaque. It’s virtually always multi-colored, and usually patterned, as well: Inclusions appear in the form of lines, waves, dots, swirls, orbs, clusters, and all sorts of geometric shapes. We’ve talked about jasper here before; some of it closely resembles agate, but it does not have agate’s translucence. And despite being part of the larger quartz family, it doesn’t appear in the sort of crystalline form common to ordinary quartz; its microcrystalline structure, much grainier, is what gives it its opacity. Jasper is found in all three types of rock — igneous, metamorphic, and sedimentary — and it co-occurs with virtually every type of mineral, as well as some non-mineral materials such as coral and dendrites.
As a general matter, it’s often easy to tell the difference between the two simply by looking at a stone’s texture: Is it smooth and glossy? Can you see through parts of it? It’s likely agate. Is it solid, grainier, perhaps resembling colorful, highly polished sandstone? Is it opaque even at the edges? It’s probably jasper. The same is true of pattern: Does it manifest in concentric bands or see-through spots? Agate. Does it have opaque, yet colorful blotches and patches and swirls and whorls? Jasper.
But what happens when the two of them appear in the same stone?
Wings acquired this cabochon as a gift, and it took me some time to determine exactly what it is. It was labeled “polka-dot jasper,” but that’s a misnomer, although many people in the mineralogical and gemological fields use it. But if you look at examples of this stone elsewhere, no matter how it’s labeled, it all bears one quality singular to agate (and not to jasper): translucence. As you can see even from the photos, this particular cabochon (which, indeed, is domed only the tiniest bit, and is really more of a highly polished free-form slab) possesses that translucence, particularly around the edges where the off-white color predominates.
That alone would seem to make this stone agate. The color combination, on one very narrow spectrum ranging from white to yellow-gold to golden brown to brownish-black, normally indicates polka-dot agate; those color combinations are its hallmark. And yet . . . .
There’s a reason it’s called “polka-dot agate.” As of this writing, you can see clear examples at this link (although they’re mislabeled “jasper”). You can also see correctly-labeled specimens here. The colors are virtually identical to those in this stone, but they clearly manifest in . . . yes, polka dots. Or, rather, round and oval dot-like patterns of inclusions. but what to make of the patterns on this one — whorls instead of dots, with feathery inclusions resembling dendrites?
Think of the two stones not as cousins, but perhaps as half-brothers, born of the same grouping of host rock, but with “genes” added from different mineralogical “fathers.” In this particular instance, agate and jasper have, over geologic periods of time, flown together into the same mass of rock, creating the sort of uniquely beautiful specimen shown here.
Polka-dot agate is found, as far as I know, only in one specific site in North America: in a formation known as the Priday Agate Beds, found in central Oregon (although it is not the only source; polka-dot agate is also found in at least one location in Africa). There, a specific mine is devoted to extracting the stone. The “polka dots” are actually inclusions of other minerals, of course, some of them metallic in nature, such as iron and hematite; which minerals are present in a given sample determine the color of the inclusions. In the case of the slab shown here in today’s post, the golden-brown bands and swatches of color are the bits of jasper that flowed into place with the agate.
It is entirely possible, of course, that polka-dot agate, including this form with jasper inclusions, has at one time or another borne special significance for the indigenous peoples of the area where it is found. If so, that significance is either lost to memory or not shared with the outside world. Some modern non-Native “crystal” practitioners, however, do impute certain properties to it, above and beyond those qualities they believe that agate and jasper possess in general terms. It appears that most such practitioners regard both agate and jasper to be “balancing” and “cleansing”; they also believe that agate is “protective,” while jasper is “nurturing.” In addition to this, it appears that some practitioners impute specific properties, such as “love,” to polka-dot agate based on the color of the inclusions in a specific stone.
For us, it’s simply a beautiful stone in the colors of autumn, one whose white ground also evokes the imagery of soft winter snows. In this particular version, the cabochon shown here today, it’s also a wonderfully unique compound of color and pattern, bands and lines and feathers and whorls that catch the light and send it shining through the stone’s translucent edges. If it speaks particularly to you, simply inquire via the Contact form; Wings can create a work with it that is wholly your own, suited to your spirit.
I said above that jasper is related to chert, a popular substance in times both ancient and not so long ago for arrowheads and spear points and other blades. This reminds me of those old points, used for both weaponry and art. In this instance, it looks like one knapped out of the fall and winter seasons themselves, a bit of still-warm earth held fast in spreading ice.
It’s a fitting stone for this threshold time of year, when the line between seasons and worlds alike is blurred and difficult to identify. Perhaps that’s the gift of a stone like this: one composed of two brothers, related yet also very much possessed of their own identities, a family relationship unified into one beautiful whole that is greater than the sum of its parts. From a material used by brothers in arms, manifest as brothers in earth.
~ Aji
All content, including photos and text, are copyright Wings and Aji, 2015; all rights reserved. Nothing herein may used or reproduced in any form without the express written permission of the owner.
