How does quartz become smoky quartz?

Before we delve into this subject, it’s important to note that all smoky quartz, natural or otherwise, is irradiated in some fashion. For natural smoky quartz, this happens due to the presence of radioactive minerals in the earth. For enhanced smoky quartz, this happens after it has been mined.

Smoky quartz gets its color from changes within the crystal produced by radiation. All quartz is made of silicon dioxide, with various colors produced by mineral inclusions within this silicon dioxide lattice. In smoky quartz’s case, this is trace amounts of aluminum, which form AlO₄^–molecules that take the place of some of the SiO₄within the crystal. If you look at the molecules, you’ll notice that AlO₄^–carries a negative charge, while SiO₄does not. Because of this, the crystal lattice of smoky quartz also contains small amounts of positive ions, usually hydrogen, lithium, or sodium. When this quartz is exposed to radiation, some of this silicon dioxide becomes free silicon and some of the electrons from the AlO₄^–molecules get knocked out of place. They hook up with the positive ions, and create the characteristic “smoky” gray or brown color of smoky quartz.

Is irradiated quartz safe?

For the most part, irradiated quartz — whether naturally or artificially — is perfectly safe. Think of the color like a suntan. A person tans because they’ve been exposed to solar radiation, but that change in color means that radiation has acted on them, not that they are emitting radiation themselves.

Notice, however, that I say “for the most part.” After typical exposures to radiation, most smoky quartz is perfectly safe. Depending on the source of radiation, some crystals have a somewhat higher risk of becoming radioactive. It’s important to note that this is still a pretty low level of radiation, and decreases with time.

For a stone to become radioactive, radiation needs to add or remove a neutron from some of the atoms within the crystal. In other words, the energy of radiation striking the stone needs to be greater than the energy needed to bump a neutron out of place. The amount of energy it takes to do this varies by element.

Neutron bombardment using a nuclear reactor can irradiate stones, though this is a relatively uncommon method. Stones produced by this process tend to be very dark, and are almost always radioactive. Because of this, these stones are not released for sale until and unless the radioactivity had decayed to safe levels. Electron bombardment using a a particle accelerator streams a narrow beam of electrons at a stone. Many of these accelerators do not operate at a high enough energy to make a stone radioactive, but some do. Even so, the radioactivity of these stones decays quickly, making them perfectly safe within a day or two of treatment. Lastly, gamma irradiators use ⁶⁰Co (cobalt 60) to produce energy. This does not meet the energy threshold needed to make smoky quartz radioactive. In fact, this process is also used to sterilize things like produce and medical equipment.

So, what does this all mean? By the time a smoky quartz has entered the market for purchase, it’s safe. Wearing or using natural or artificially irradiated smoky quartz is not going to hurt you. If it emits any radiation at all, it will be minimal compared to natural sources of radiation that you come in contact with every day — radioactive minerals in granite, or the potassium isotopes in a banana, for example.

How can you tell if a smoky quartz has been artificially irradiated?

Unlike heat-treated amethyst, there’s really no good way to tell. Some natural varieties of smoky quartz are very dark, like morion, so you can’t always go by color. This means that, unless the stone is labeled or the dealer tells you, the only way to tell if a stone has been artificially irradiated is by examining the matrix.

Naturally-occurring smoky quartz is found adjacent to minerals that contain radioactive material. This usually means intrusive igneous or metamorphic rocks (like granite, an intrusive igneous stone). On the other hand, radioactive material is less common in sedimentary rock like shale (with the exception of uranium, which can appear in limestone, dolomite, or sandstone, among others). This means that very dark smoky quartz with a sedimentary matrix is more likely to have been artificially irradiated, though that’s not really a hard and fast rule.

Smoky quartz is a very popular and versatile stone, and it’s easy to see why — it’s as abundant as it is beautiful. Despite its abundance in nature, some stones are irradiated to improve their color, which has made some people question their safety as jewelry or healing stones. Don’t worry, though — even after getting a radiation tan, smoky quartz is perfectly safe to handle and use.

From what I have seen, citrine is like wasabi or olive oil — it’s entirely possible for someone to love it without ever having actually used it. That’s not to say that a lot of citrine crystals on the market are fake, as in made of resin or glass, just that not everything labeled as citrine is actually what it says it is.

What is citrine, really?

Citrine crystals are best known as a bright, sunny yellow variety of quartz. Nobody is really sure where the color comes from. Some suggest that it’s caused by iron impurities in the crystal’s structure, while others say it’s more likely caused by aluminum or irradiation. From what I’ve been able to gather, there are probably several varieties of yellow quartz created under different conditions, all of which have been lumped together for the gem trade under the name “citrine.”

Metaphysically, it’s a stone often used for prosperity, luck, and success spells. Its sunny color lends well to everything relating to the yellow, gold, and orange areas of color magic. As a healing stone, it brings positivity and optimism.

How is citrine faked?

Real citrine is pretty rare. It doesn’t seem so when you walk into a crystal shop, though — chances are, there are tons of clusters of bright orange crystals, usually at a very reasonable price. So, what gives?

While citrine is uncommon, amethyst is not. It’s not at all unusual to take amethyst, subject it to heat treating, and get something that can pass for citrine — in the sense that it’s a crystal, and yellowish.

How can you tell if a citrine is real or heat-treated?

To put it bluntly, if you’re used to seeing heat-treated amethyst, real citrine is… Well, disappointing. Most of it looks closer to a smoky quartz than the vibrant orange hues of the heated stuff. It’s like looking at a glass of orange juice next to a glass of orange soda. Compared to a glowing yellow heated amethyst cluster, the real stuff looks almost anemic.

There are other ways to tell, too. Real citrine:

Does not often have the same growth habit as amethyst. While we’re probably all used to seeing clusters of low-growing amethyst crystals that look almost like grape jelly, citrine usually appears with longer, straight crystals or as individual points, more akin to clear quartz.
Tends to vary between a light yellow, like white Zinfandel, to a smokier, apple juice color. It doesn’t naturally have that bright orange appearance.
Tends to be very clear.
Is pricier than heated crystals.

By contrast, heat-treated crystals:

Tend to have a very milky base, or be cloudy throughout.
Often show up as pieces of geodes, usually with a very white base. Individual points usually have a very triangular, almost toothlike appearance.
Are extremely brightly colored.
Don’t cost much.

There’s one other way to tell a citrine from a baked amethyst — pleochroism. It’s not something the average crystal-buyer can really use to their advantage, but it’s much less subjective than determining how clear a crystal is, or exactly where it falls in the range of natural and artificial colors. Pleochroism describes an optical phenomenon where a mineral appears to change colors when viewed from different angles, particularly when using a polarized light source. Amethyst, citrine, and smoky quartz are all pleochroic. Heating amethyst to alter its color causes it to lose this property, so it is consistently yellow (or orange, or brownish) regardless.

Interestingly, citrines created by heating smoky quartz do continue to exhibit pleochroism. These citrines also become pale when they are heated further, and turn yellow when exposed to radiation.

Does it really matter?

Well, yes and no.

Some argue that heat treating a crystal is just exposing it to the same effects that would happen naturally, so the end product isn’t actually any different from a genuine citrine. Others say that that isn’t the case, and the natural circumstances of a crystal’s formation influence its properties.

If you’re looking for a bright yellow or orange crystal because you want to tap into the magical properties of those colors, it probably doesn’t matter how the crystal was made. If using things in a raw, unadulterated form is important to you, you probably want to shy away from artificially colored crystals. The choice is ultimately up to you.

It matters to me because, under the right conditions, you can tell the difference between a heated amethyst and a citrine. Pleochroism is an empirical way to tell which crystals are baked amethysts, and which are not. I feel like this is an important distinction — magic is transformative. Natural citrine takes in light, and shifts its color based on how its viewed. A crystal that’s supposed to be pleochroic and isn’t wouldn’t be as useful to me as an unaltered stone.

From a practical standpoint, it can also matter because heating a stone affects its durability. High heat can alter the matrix, especially of crystal clusters, making it chalkier and more prone to crumbling.

Color magic is a deep and fully developed magical system of its own. If the color is all that matters to a spell, it doesn’t really matter whether a stone is natural, heated, dyed, or coated. For witches who prefer to work with stones in an unaltered state, the distinction between natural and heat-treated citrine can be an important one.

Tag: heat treated crystals

Irradiated Smoky Quartz: Is it really safe?