Do you know these Gemstones are dyed?

Gemstone Dyeing or Staining

Aside from stone durability, luster, patterns and crystal habits, and designs, one important feature that makes natural gemstones truly desirable and beautiful is their color. In fact, when choosing and shopping for gemstones, many would look at the stone color and saturation first - and all other feature checks would just follow. However, even when gemstones are void of the synthetic and are purely natural, not all of them display vibrant and brilliant colors - those that appeal to the eyes of customers easily and most often. Which is why, some gemstone dealers and suppliers resort to one technique to address such concern - gemstone dyeing.

There are actually quite a considerable number of gemstone treatments and techniques to enhance the appearance of lower-grade gemstones, particularly those with slightly dull and plain hue and saturation. One of which is dyeing - or sometimes referred to as ‘staining’ - of gemstones. This traditional gemstone enhancement method can temporarily influence the stone’s exterior display, but sometimes it can also be permanent, making the stone completely different from what it used to be.

The dyeing or staining of gemstones is one of the oldest gem treatments, but it is one of the most commonly and widely used. This technique involves introducing colored dyes into poriferous or fractured gems to change - and enhance - their color. Such fractures are sometimes purposely induced by heating the gem, for the otherwise non-porous material can readily accept the dye more.

There are also stones that are porous only to a minimal extent. This condition allows the colored dye solution to only affect mostly the exterior of the stone, and prevents it from penetrating into the stone. Under such circumstances, you would see that the center of the stone is not stained after cutting.

Sometimes, to perform successful gemstone dyeing, stones are boiled in a strong bicarbonate dye solution. The heating causes the stone to expand, which makes any pores or fractures to be more easily penetrable. Sometimes, too, heated or hot stones are subtly dropped into cold solutions in order for the sudden temperature change to cause existing fractures to propagate through the stone. These fractures are important as they serve as channels for the dyed solution to penetrate.

Commonly Dyed Gemstones

When you ask which gemstones undergo the dyeing process for enhancement, we could provide a handful. However, the full list might just be very overwhelming, so we will introduce some common dyed gemstones instead. This can help you have better recognition of the stones for better and more informed gemstone selection.

1 Chalcedony

Chalcedony is a cryptocrystalline form of silica that has been known since antiquity. The stone usually has a waxy and greasy luster, with diaphaneity that is either semitransparent or translucent. Chalcedony can occur in different range of colors including yellow, purple, green, orange, black and banded, but it more commonly comes in shades of grayish-blue, white to gray,  or a shade of brown.

Because of its porosity, Chalcedony is a popular choice for gem dyeing. The stone’s void spaces are significant, therefore creating brilliant and bright version of the stone after the dyeing process.  With Chalcedony, not only does dyeing  bring about the vibrant version of the stone’s saturation; it also enhances the stone’s overall appearance and make it look semi-transparent - like glass - and pure.

In fact, some fake chalcedony are made of glass.

2 Agate

Agate is stone with traces of chalcedony and quartz, and are formed primarily within metamorphic and volcanic rocks. This stone is usually transparent, with colors dominantly characterize of bands and patterns. However, Agate is also widely known for its rather dully, milky appearance.

Like Chalcedony, Agate is a porous stone, and is one of the widely dyed stones in the gem industry. Because of its natural dull saturation, Agate does not look as appealing as other stones. This is why gem dealers and suppliers apply colored dyes to enhance the stone’s beauty.

As a result, dyed Agate stones display bright and vivid colors - those that are really pieces of eye candies. However, these new colors of the stone made from the dyeing process sometimes blur the boundaries between color bands - bands that sets the Agate stone unique from other gems. Also, color accumulation in the rather tiny cracks of the stone is also conspicuous when observing and examining stone closely using a magnifying glass. 

3. Tiger’s Eye Stone

As its name suggests, Tiger's Eye is a gemstone that is commonly defined by its gorgeous yellow-golden bands that are noticeable in silky shimmers. However, aside from the common ‘golden’ Tiger’s eye, the stone can also come in mid blue to dark blue colors. This variety of the Tiger’s Eye is called the Blue tiger’s eye (also referred to as the ‘Hawk’s Eye’).

As like the previous stones tackled, Tiger’s Eye is also a good candidate for gemstone dyeing. This is because the stone, as a member of the quartz crystal family, has porosity that makes colored / dyed solution penetrate it easily to impart a particular tinge.

Aside from dyeing, heat treatments can also affect the physical appearance of the Tiger’s Eye stone. And besides blue and yellow-gold, the stone can also assume a red brown color after being gently heated. 

4 Howlite

Howlite is a borate mineral, and is commonly found in evaporite deposits. Generally, this stone is widely known for its white (absorbent) color, with interesting grey, brown or black veins and specks.

Howlite is characterized by considerable porosity, it can easily absorb colored dye solutions or any stained liquid for that matter. The most common color Howlite is dyed with is blue or the Robins egg blue that makes the stone look similar to a Turquoise. But these two (Turquoise and dyed Howlite) are significantly different in so many ways including the webbing nature, durability, and color distribution among others.

Dyed Howlite, like any other dyed stones, have seemingly uniformed color distribution, while a Turquoise stone’s color gradient changes depending on the amount of Copper elements it contains.

Because Turquoise is a valuable gemstone, some sellers deal blue-dyed Howlite as Turquoise at a relatively lower price. It may sound too good to be true, but why not, right? After all, they are not the natural, expensive Turquoise buyers expect them to be. This is why it is very important for gem buyers and enthusiasts to be educated and informed, in order to avoid scams. 

5. Amazonite

One dazzling gemstone with soft green to blue green color that have white streaks on them is Amazonite, sometimes called either the Amazone Stone or Amazon Jade. Although the stone is innately beautiful, with its soothing natural color, some gem sellers find it equally important to dye the stone into more brilliant and much bluer perfection. Thus, making the most of Amazonite’s porous characteristic.

When an Amazonite is dyed, the stone is expected to exhibit a uniformed bluer color now devoid of the white streaks. The dyeing process also makes the stone become transparent.

Dyed Amazonite stones are appealing to those who want their Amazonite loose stones, cabochons or beads to look very alike and glassy, while those who find the natural greasy and ‘creamy’ blue to blue green appearance of the stone find the dyed ones less desirable.

With Amazonite stone, distinguishing the natural one from the dyed stone is quite easy. The process would not require one to examine the stone closely through a magnifying glass, or to observe the minute cracks the stone (like others) may have. White streaks and patches are among the defining assets of a natural Amazonite, and such feature is absent in the dyed version of the stone. The latter are presented in loose stones, cabochons, or beads that all look very alike - with glassy blue-green color sans any white streaks or patches present as in the pictures below. 

6 Lapis Lazuli

Lapis Lazuli is an attractive deep-blue semi-precious gemstone that has been popular since the olden days. This stone is often mottled with white streaks of calcite and brassy patches of pyrite that make it even more splendid. However, although Lapis is already an item of regality with its deep-blue saturation, there are still some who want the stone’s blue to be enhanced even more, especially those that have poor color quality; thus, the dyeing of the Lapis Lazuli stones.

When Lapis Lazuli is dyed, the outcome is a more intense deep-blue-colored stone that, honestly, appears more elegant than the natural one. However, the problem now lies in how the dyeing process gets rid of the beautiful mottling effect of the Lapis stone. Truth be told, after the dyeing process, the Lapis Lazuli stones become uniformed that one loose stone would look a lot like the others in the batch. Also, the process inhibits the stone of its attractive white calcite and gold pyrite streaks, thus making it less lively and dynamic.

A close look at a dyed Lapis Lazuli will make you notice that the dyed color is enriched along the gaps. 

7. Turquoise

Because of the relatively high profit one can get from selling them, Turquoise stones are probably among the most replicated or ‘faked’ stones in the gem industry.

Although the stone is already a beauty in its natural exterior, there are varieties of Turquoise that lack appeal and vibrance. These varieties, those deemed to have poor qualities, are the ones that are usually dyed in order to improve their color, make them more uniformed and attractive. With the stone’s porosity, colored dye solution can easily absorb the stone and impart color.

Some stones that are mistaken for - and sometimes being deceitfully dealt as - a natural Turquoise include compressed Turquoise powder and industrial resin adhesive, dyed Turquoise-colored Howlite, dyed Turquoise-colored marble, dyed Turquoise-colored glass, dyed Turquoise-colored plastic, etc., and some natural turquoise color non-turquoise gemstones. 

How do you tell if the gemstone is dyed?

Identifying natural gems from dyed ones is only hard and confusing at first, but when you get to familiarize yourself and be educated about them, such task becomes easy.

Here are some easy-to-remember tips to recognize which gemstones are natural and which ones are dyed.

• Most dyed stones can be easily recognized by their appearance. Many of them have very bright and outrageous colors - colors that are pretty off when talking about natural gemstones. Also, dyed stones look a lot like each other, and mostly have uniformed and equal color distribution. Natural ones, on the other hand, rarely exhibit this property as most of them have unequal color distribution depending on the chemicals and elements they contain.

• When you look at a dyed stone, you would see colored dye accumulating in the stone’s pits and fractures. The dyed solution gets stuck in these cracks and they can be easily felt.

• Another way to identify whether a gemstone is natural or dyed is to test its color stability. Using acetone or nail polish remover on a cloth, cotton or tissue, wipe the (insignificant) surface of the stone - maybe the back - and see if the color (dye) sticks with the cotton and if the wiped surface of the stone turns white. If it does, you can know there and then that it is definitely not a genuine one.

• As it has been previously highlighted, price is a factor that pushes some gem sellers and dealers to resort to stone dyeing. This is often done in order to replicate high-priced stones and sell the replicas at a much lower price. However, in this case, price is also a significant indicator that a gemstone is natural or not. Statistically speaking, genuine and natural gemstones are priced relatively high. Thus, if you see a variety that is being sold cheap, it is -more often than not - just a dyed stone and not authentic.

• Lastly, dyed stones also tend to leave botches and color traces on the cords or strings that are used to put them together to make a jewelry piece. Natural gems, on the other hand, do not exhibit this characteristic. 

Takeaway Message

We value our customers, that is why we are trying to help them by educating and making them informed about the important factors to consider in purchasing any gem and jewelry-making material. This is to promote a healthy transaction wherein nobody is taken advantage of.

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