Gemstones

Smoky Quartz Guide

If you have ever looked through the quartz selection at a rock shop and spied a dark grey, brown, or black variety of quartz, you may have seen a specimen of smoky quartz.

Smoky quartz is a popular form of quartz for jewelry and general collecting purposes, and is a close relative of another form of quartz called citrine.

TABLE OF CONTENTS

What is Smoky Quartz?

Some smoky quartz is so dark it looks black. This is often called 'morion'

Some smoky quartz is so dark it looks black. This is often called ‘morion’ – Image credit to Eurico Zimbres – CC BY-SA 2.5

Smoky quartz is a silicon dioxide mineral. Gamma irradiation causes aluminum traces to accumulate in the lattice, displacing some of the silicon. This results in smoky hues.

Smoky Quartz Properties and Color

Smoky quartz crystals often form as six-sided prisms and terminate in pyramids, but many crystal formations are possible (no needle-like crystals however). Like other forms of quartz, they are brittle and have a vitreous luster. On the Mohs scale of hardness, quartz is always a 7.

In terms of transparency, smoky quartz may be completely transparent with a glassy look, or it may range through various levels of translucency to complete opacity.

Some pieces have translucent and clear parts; these scattered cloudy areas coupled with the “dirty” hues are exactly what lend the impression that there is “smoke” inside the quartz.

In terms of color, you will see quite a bit of variation in smoky quartz pieces. Some are a very pale tan color, while others are a medium brown or grey. Still others are so dark as to be almost black or black. One specimen may exhibit a single hue or a range of hues. Whether a specimen is a single color or features multiple hues generally depends on how and where it formed. Evenly-colored crystals tend to form in pegmatites, alpine-type fissures, and other high-temperature settings. Smoky quartz formed in other environments will usually exhibit more than one color.

Additionally, smoky quartz exhibits a dichroic effect in the presence of polarized light. When you rotate a smoky quartz crystal in polarized light, you will notice a color change.

Smoky quartz is unstable, and if exposed to heat, its colors will pale. The same can happen with prolonged exposure to UV light. This process can be reversed and the colors darkened again through a process of gamma irradiation.

Smoky quartz on an orthoclase matrix

Smoky quartz on an orthoclase matrix

Special Types of Smoky Quartz: Morion and Cairngorm

There are a couple of types of smoky quartz which are distinctive enough to have their own unique names.

The first of these is called “morion.” This word is a misreading of “mormorion” from Pliny the Elder. It is a synonym for smoky quartz in the Danish, Spanish, German, and Polish languages. The word is used elsewhere to refer specifically to smoky quartz which is so deep and dark in color as to be opaque. Morion may occur in very dark brown or in black.

Another famous type of smoky quartz is “cairngorm.” This type of smoky quartz is named for the location where it is mined, the Cairngorm Mountains of Scotland. Specimens are usually yellowish-brown, but may also occur in a greyish-brown color. Cairngorm crystals can be quite sizable; the largest known piece weighs 52 pounds, and is housed in Braemar Castle. Cairngorm is traditionally used in Scottish artisan crafts, and adorns jewelry, kilt pins, and knife handles.

Erroneous Classifications

It is actually quite easy to confuse smoky quartz with other forms of quartz. For example, in Italy and Spain, limestone, gypsum, and anhydrite sedimentary rocks have been discovered which are embedded with black quartz crystals. These black quartz crystals may look identical to smoky quartz, but their color comes from inclusions—not from the displacement of silicon by aluminum resulting from gamma irradiation.

How can smoky quartz be distinguished from similar-looking specimens of quartz which formed through different means? One of the easiest ways to tell is by looking for dichroism. Smoky quartz will exhibit this effect; look-alike specimens will not.

Smoky quartz crystal

Smoky quartz crystal – Image credit to David Björn – CC BY 2.0

What is the Link between Smoky Quartz and Citrine?

There is another form of quartz known as citrine which typically occurs in a golden orangey color. There is some variation in citrine’s coloration however, and some specimens may be brownish—rather like smoky quartz.

While researchers are quite clear on what causes the color of smoky quartz, they are less certain what gives citrine its color. In fact, there may be more than one cause of color in citrine—so those pieces that appear the same color as smoky quartz may actually be formed the same way. In short, these are overlapping categories. Some pieces of citrine which are brownish in color are sold as smoky quartz—and may actually be smoky quartz.

Like smoky quartz, citrine may be heat-treated or irradiated to pale or deepen its color. In fact, smoky quartz specimens which are treated properly can actually be converted into citrine—just like amethyst, the stone which is most commonly used for this purpose.

There is even an “in-between” variety of stone which is referred to as “smoky citrine.” As you might expect, this transitional gemstone exhibits the characteristic murky look of smoky quartz, but it has something of the yellowish tint of citrine.

Smoky Quartz Uses

Fascinatingly enough, smoky quartz was used to create sunglasses in the 12th century—more on that in the history section.

Smoky quartz is no longer used for sunglasses. Instead, it is used for ornamental purposes. It may be displayed in its raw form in gem collections, or it may be crafted into jewelry. Smoky quartz may also be carved into figurines. It is particularly well-suited to this purpose because of the variations in its hues. Those variations can help to bring out the contours of animals, plants, skulls, and other objects. Many pieces are quite elaborate and beautiful.

Stunning smoky quartz (morion) crystals

Stunning smoky quartz (morion) crystals – click for a larger image – Image credit to Dario Crespi – CC BY-SA 3.0

Smoky Quartz Buying Guide

When shopping for smoky quartz, there are a number of criteria to consider, but no hard rules. When buying a diamond, you are taught to look for the four Cs: color, cut, clarity, and carat. With smoky quartz, you will obviously pay more for larger pieces, but carat is still not that big a deal considering how common large specimens of smoky quartz are.

What about color, clarity, and cut? Well, color is quite subjective. Some people like the classic medium brown or greyish smoky color, while others prefer the paler tan pieces or the dark morion specimens. Still others prefer smoky quartz with a yellowish hue (like smoky citrine or Cairngorm).

In terms of clarity, personal preferences also are important. You may like relatively clear pieces, or you may prefer those with the smokier or more opaque appearance. Quite often the most interesting specimens are those with a range of colors and patches of varying translucency.

The cut of a smoky quartz gemstone can also be important. While tumbled smoky quartz and raw pieces are both very popular, you will sometimes find faceted smoky quartz as well. For the clearer, inclusion-free pieces, the cut can help to bring out the best.

Smoky Quartz Value

What will you pay for smoky quartz? The cost can vary quite a bit depending on what you are trying to buy. If you are shopping wholesale for rough or tumbled pieces, you can get some outstanding deals. You can purchase a huge strand of smoky quartz points for just a few dollars.

If you are buying raw crystals however and you are looking at larger pieces which feature exquisite natural beauty, you should expect to pay quite a lot—hundreds or thousands of dollars.

What about faceted smoky quartz gemstones? These are generally quite cheap. You can even purchase them wholesale. You might get around 40 pieces for under $30. If you are a jeweler, smoky quartz makes an excellent choice for keeping your raw materials cost down while still producing beautiful pieces.

Faceted smoky quartz gemstones are generally quite cheap

Faceted smoky quartz gemstones are generally quite cheap – click to zoom in – Image credit to Kotomi_ – CC BY-NC 2.0

Smoky Quartz Jewelry

You can find smoky quartz made into just about anything. Because large specimens are available, smoky quartz is ideally suited to pendants and brooches. It also works great for necklaces and bracelets as well as smaller pieces like earrings and rings.

Along with faceted pieces, those which have been tumbled and polished are particularly popular for pendants. Smoky quartz may also be rounded into beads for stringing. Carved pieces may sometimes be used in smoky quartz jewelry creation as well.

Smoky quartz earrings

Smoky quartz earrings – Image credit to Cathy Wellman – CC BY 2.0

Smoky Quartz Engagement Rings

Considering how easy it would be to mistake smoky quartz on sight for a brown diamond, it may surprise you that they actually seem to be used quite commonly for engagement rings. They are not a popular choice, but you will find a surprisingly big selection.

Both the darker and lighter specimens may be set in gold, sterling silver, copper, or other beautiful metals. Typically they are encrusted with small white diamonds. These offset their colors and add value to the rings.

Pros:

  • For a recipient who loves brown, smoky quartz is a beautiful and distinctive choice. It does accompany certain metals particularly well, like rose gold and copper.
  • A smoky quartz gemstone will not carry a high cost on its own, so most of the money you spend will be on the band. This gives you the chance to purchase something more ornate than you might be able to afford if you were buying a diamond.
  • If the central stone is damaged in any way, replacing it is pretty easy and cheap.

Cons:

  • Smoky quartz works beautifully with some skin tones and wardrobes, but will not be a great color match for everyone.
  • Smoky quartz may be mistaken for a brown diamond. Some people do like brown diamonds, but a lot of people hate them. This may be particularly problematic with the lighter tan-colored smoky quartz. Worse than appearing as a brown diamond, these may simply seem like low grade “colorless” diamonds with a strong brownish tint. This may cheapen the appearance of the ring. Ironically, in terms of value, it is easier to forgive an “expensive” smoky quartz for being cheap than it is to forgive a “cheap” diamond.
  • On the other hand, the reputation of smoky quartz as a “cheap” stone may be offensive to some recipients. Plus, smoky quartz is nontraditional, and for many, only a diamond will do.
  • As smoky quartz is a 7 on the Mohs scale of hardness, it is not the best choice for everyday wear. It is a brittle stone and may fracture if it is banged against a surface. It can also be scratched by other harder gemstones.
Smoky quartz ring from Brazil

Smoky quartz ring from Brazil – Image credit to Mauro Cateb – CC BY-SA 3.0

How to Clean and Store Smoky Quartz

  • Cleaning Smoky Quartz: You should avoid cleaning smoky quartz with an ultrasonic or steam cleaner. Cleaning it by hand will protect it as well as the setting. A soft toothbrush is the best choice if you need to do some scrubbing; use a solution of warm water and mild detergent. Once you finish cleaning, use a soft cloth to mop your piece dry, or you can just let it air-dry. To clean the setting, use a jeweler’s polishing cloth.
  • Storing Smoky Quartz: Take extra care when storing smoky quartz. Because the piece may be scratched by other jewelry, it should be placed in a separate compartment. Be sure to keep it out of direct sunlight and heat, as these may result in color changes.
  • Wearing Smoky Quartz: Be careful when wearing smoky quartz too. Take it off before doing any work with your hands so that you do not risk scratching or fracturing the gem. Do not expose it to harsh chemicals in detergents, and keep it away from cosmetic products as well.
"Morion" quartz from France

“Morion” quartz from France

Smoky Quartz Video


Beautifully cut smoky quartz gemstone – 13.62ct Barion Oval

Smoky Quartz History

As mentioned previously, smoky quartz had quite an intriguing historical application: it was used to make of sunglasses.

We generally think of sunglasses as something thoroughly “modern,” but in reality the history of sunglasses dates all the way back to prehistoric times. Back then, Inuit tribesmen pioneered primitive shades out of flattened ivory harvested from walruses. Ancient Romans also wore sunglasses after a fashion—there are historical accounts of the emperor Nero viewing gladiatorial fights on bright days through polished gems.

In China during the 12th century, sunglasses design evolved with the help of smoky quartz. The flat glass panes which were used bore a close resemblance to what we use today. Unlike our modern sunglasses, they were unable to offer any UV protection, but they did block out the bright light and provide some comfort on sunny days.

Interestingly enough, that was not their only application either. Today, many people enjoy wearing sunglasses to hide their eyes. This provides a sense of privacy and conveys a sense of distance, power, and superiority. In ancient China, judges in courts often wore sunglasses made out of smoky quartz for just this reason. It was a way for them to maintain their distance and hide their expressions.

Aside from that key role, smoky quartz isn’t known to have played any particularly important role in history. It hasn’t been until relatively recently that it has become a popular choice for jewelry.

Smoky Quartz Meaning

Smoky quartz is considered an excellent gemstone for grounding and centering. It is regarded as a very soothing gemstone, one which can provide comfort during times of stress. Some metaphysical practitioners believe that it can ward off nightmares.

Smoky quartz crystals from Switzerland

Smoky quartz crystals from Switzerland – Image credit to Eva K. – GFDL 1.2

Similar and Related Gemstones

Smoky quartz is a fairly distinctive gemstone, so you are not all that likely to mix it up with others. Even so, there are a few gemstones which are similar enough in appearance that you may occasionally confuse them.

  • Citrine. As discussed earlier, citrine isn’t just a similar-looking gemstone—it is one which is actually related to smoky quartz. At the “midway” point between the two, you can even find “smoky citrine.”
  • Black quartz crystals. As also discussed previously, there are certain black quartz crystals which may sometimes be confused with smoky quartz. Their color however comes from inclusions, not from irradiation, and they do not exhibit dichroism as smoky quartz does.
  • Melanite garnet. This is a form of granite which is black in color with a glossy sub-metallic luster. It is also referred to as “titanian andradite” because of its titanium impurities. It is classified as a type of “demantoid garnet,” a name which references the brilliance that stems from its high refractive index. In terms of hardness, it is similar to smoky quartz.
  • Schorl Tourmaline. This mineral is more commonly known as “black tourmaline.” Black is a color which occurs in several forms of tourmaline, but quite often in conjunction with other colors. Schorl on the other hand is entirely black, and always totally opaque. Other forms of tourmaline are typically translucent or transparent. Its brilliant luster and attractive crystals make it popular among collectors. It ranks a 7-7.5 on the Mohs scale of hardness, making it slightly harder than smoky quartz. In its raw form, tourmaline crystals are quite distinctive in shape and readily recognizable from quartz crystals.
  • Brown topaz. Topaz is a popular and highly prized gemstone which occurs in a wide variety of colors. Like quartz, it has a glassy luster, but it is harder, ranking 8 on the Mohs scale. At a glance, brown topaz can look quite similar to smoky quartz.
  • Brown diamond. Brown diamond may also be confused with smoky quartz, but there are a couple of giveaways. Diamond has fire, and smoky quartz doesn’t. You are not going to see the same sparkle in the facets of a polished quartz gemstone. Diamond is also significantly harder, ranking a 10 on the Mohs scale.

While many gemstones are prized for their perfections, smoky quartz is actually valued for its imperfections. Crystals which feature a range of smoky hues are particularly eye-catching. They look beautiful in display cases, and make a gorgeous statement in jewelry.

Smoky quartz makes an affordable and stunning addition to any collection.

Smoky quartz from Brazil

Smoky quartz from Brazil

Resources

Smoky quartz from the Museo di storia naturale in Florence

Smoky quartz from the Museo di storia naturale in Florence – Image credit to Sailko – CC BY-SA 3.0

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