Mineral & Gemstone Treatment

Mineral & Gemstone Treatment

Mineral & Gemstone Treatment

All gemstones on the market are treated. That's right. A gemstone, by definition, is cut and polished. That means we've treated it or altered it in some way. You might say that's setting the bar low. That's fair. But even aside from cutting and polishing, you'll find that many stones are treated. That said, this has to be disclosed in some way.

We often get asked about stone treatment and whether or not minerals are "natural." There's a lot of linguistic or semantic strike and parry going on. By definition, a mineral is natural. So, if we have a man-made "mineral," we disclose that. Still, we've seen a lot of flaming against treated or altered minerals.

A lot of this hatred stems from misconceptions and the assumption that treatment must mean it's bad since it's not "natural" or "organic." This is a complete misunderstanding of how the industry operates. Let's get into the details.

Treatment Bad

A lot of comments we see equate treatment to bad. We'll get into the why of that later. Treatment doesn't mean bad. A lot of stones are treated so they can look more appealing when on the market. That doesn't mean "natural' minerals are ugly (though they can be). It just means that some stones could use a little more color clarity or reducing inclusions. Plus, a lot of stones aren't perfect.

Let's take a look at diamonds as an example, since they are a staple of the gemstone world.

Diamond in tongs or tweezers

Beautiful, right? Well, if you happen to think diamonds like this are beautiful but hate treatment, we have bad news for you.

If you regularly shop for diamonds, you have almost certainly heard of diamond treatment. Many, many, and yes, many diamonds on the market are treated in some way. But it's such a vast industry that going into details on it is well out of the scope of the article.

Why would someone ruin the precious beauty of a natural, raw diamond? Probably because they look more like this.

Rough diamond

That's still a decent case scenario. A lot of diamonds are just not appealing enough to even make it close to the gem market. Those that are completely natural and hideous are almost certainly ground up for industrial use.

Alright, before we get into diamonds even more, let's get back to the point. Treatment doesn't mean bad. To get a diamond from the second image to the first, you're going to have to cut it, which is altering it in some way. We cut diamonds to make them show off the brilliance that pretty much everyone associates with diamonds.

You can prefer a rough stone (and many people love buying rough stones), but that doesn't mean stones treated to enhance color or clarity are inherently ugly or bad.

The Opposition

There are two main camps we can think of when it comes to hating stone treatment—those who hate stone alteration, period, and those who hate deception. There is some overlap, but let's talk about the first camp.

The first camp sees treatment as verminous. There are various reasons why. Some see it as ruining the natural beauty or integrity of the stone. Others see it as a kind of legal lying. Others, relating to the crystal healing community, thinks that treated stones have lost their magical or metaphysical powers. Finally, there are cynics when it comes to the gemstone industry, viewing the whole thing as unethical, and there are also conservationists who think we humans have no right to go traipsing around and pulling these minerals out of the earth.

Whether you prefer "raw" or treated is entirely personal preference, and whether you agree with this first camp is just belief. But we ask: are there any valid concerns about treatment?

Yes. There are very valid reasons to hate this practice. This second camp hates the deception of treatment in the industry but not necessarily the treatment itself. This group hates that a lot of sellers don't disclose that the stones are treated, which vendors are required to do.

Not disclosing that the stones are treated is deceptive and gives a false impression of the quality and value of the stone.


Herkimers with oil under a UV light

Types of Treatment

Gemstones receive treatments for a wide variety of reasons. Often, these are done for clarity, color, beauty, to remove inclusions, and much more. There is also no single procedure that works for all stones necessarily. Often, the color treatment for tiger's eye is bleaching. Topaz and diamonds, on the other hand, will likely have a surface coating for their color treatment. Still, we can try and give you a basic overview of the most common types of treatment.

Bleaching alters a stone's color. Used for a few stones. While this can enhance their visual appearance by enrichening some colors and removing others, the acids can damage the stone's integrity, making them more prone to damage. Pearls, jadeites, and anglesites are commonly bleached. It can be difficult to determine how much a stone has been bleached.

Dyeing is perhaps the most well-known style of treatment for how ubiquitous is would appear to be, even among those who don't know much about stones. However, dyeing is done to a wide variety of stones and minerals that have the soft, porous qualities necessary for the treatment to take place. While howlite, obsidian, and various chalcedonies are common, it's even done to pearls, corundums, lapis lazulis, and much more.

In some cases, it's very easy to detect if the chemical or physical properties would otherwise not lend the stone to having the color of choice when dyed. For instance, blue is a common choice for howlite to make imitation turquoise. Howlite isn't naturally blue; thus you can conclude that blue howlite is dyed.

Even in light or uncommon cases, many experts can easily determine if a stone is dyed. The biggest concern with many people who have dyed stones is when the dye dissolves, which can be messily and accidentally undone with long exposure to sunlight, alcohol, acetone, water, or a humid environment. This all depends on the dying process done, so be careful.

High-Temperature, High-Pressure Treatment (HTHP) is a lesser-known form of treatment for non-experts. This treatment is done in certain diamonds to turn them from brownish to colorless. Various colorless diamonds on the market have this treatment, and it is fairly hard to determine without some rigorous laboratory testing.

Surface Coating is an old technique that enhances the color of a stone. This is famously associated with diamonds. Historically, it was done to a wide variety of gemstones. Kinds of paints were applied in the past, but these days a film coating works well, too. Depending on the quality, skill of technique, and location, it can be difficult to uncover a coating. However, skilled gemologists will have no problem determining if a stone has been coated.

Heat Treatment is a technique that changes color and clarity with exposure to high temperatures. While amethyst as heat-treated citrine is one of the most infamous examples of this, this treatment is used on all sorts of minerals or stones, such as ambers, rubies, quartzes, sapphires, topazes, and more. Certain tests and examinations on physical or chemical structures can determine if a stone has been heat-treated.

The Wrap Up

There are numerous types of treatments when it comes to gemstones and minerals. Each has their own purpose or value, as not one solution is good for all.

Many oppose gemstone or mineral treatment, and they believe it is a deceptive practice. Regardless of where you fall, we hope that you have enjoyed this article!

Pearl strands and earrings on table display

Nathália D’Elboux Bernardino, Celly M.S. Izumi, Dalva L.A. de Faria, Fake turquoises investigated by Raman microscopy, Forensic Science International, Volume 262, 2016, Pages 196-200, ISSN 0379-0738, https://doi.org/10.1016/j.forsciint.2016.03.041.




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