‘Tourmaline’ originates from the Sinhalese word tummala, meaning mixed-colored stones, named so because tourmalines were often confused with other gems and can easily be faked, hence buyers should know how to differentiate if Black Tourmaline is Real or Fake.
Tourmaline belongs to a family of related minerals, all having essentially the same crystal structure but varying widely in chemical composition, color, and properties. Some tourmalines are appreciated as gemstones due to their colors and rarity.
95% of the Tourmaline in the earth crust is from the schorl-dravite series. It is black to brown and can occur in different geologic settings. Therefore, black Tourmaline is commonly called Schorl.
The industrial use of black Tourmaline, in the last 20 years, has been growing. It is being used in air and water purifiers, cosmetics, textiles, paints, and agriculture.
Due to its versatile nature, market demand for Black Tourmaline has aggressively shot up. Although it is rarely imitated, Black Tourmaline may often be confused with other similar-looking black rocks and glass and may even be dyed to look deeper and more prosperous.
Due to its ready availability, synthetic production of Black Tourmaline in labs is not very economically viable. Therefore, the threat of artificial material being sold as Black Tourmaline is relatively low for this gemstone.
However, its high regard as a collectible stone may be faked in materials vastly different from natural Schorl’s physical and optical traits, such as glass and plastic. Read on to understand what physical properties you need to look for to avoid buying fakes and low-grade stones.
How to tell if Black Tourmaline is Real or Fake
Observe the Luster of your Stone
Tourmalines, regardless of their mineral composition, have a vitreous luster, which means that when their surfaces interact with light, it gives a glassy finish. One way to identify fake Schorl, a black-colored Tourmaline, is that the fake stones are often marketed as having metallic or matte luster to them, which is likely to be a fake opaque black rock.
Check for Hardness
Black Tourmaline is incredibly hard, with a hardness of 7 on the Mohs scale. If you are procuring an uncut specimen, you can check its authenticity by scratching it against the glass.
If it leaves a scratch on the glass, it is a real Tourmaline. Fakes sold as Tourmaline are typically made of glass or plastic and will not be able to scratch themselves.
Observe Cleavage Planes
Cleavage indicates the tendency of a crystal to break along concrete plane surfaces.
If you are buying an uncut piece of Black Tourmaline, this should be the stone’s most visible physical and tactical feature. Real Black Tourmaline has indistinct unidirectional cleavage and looks rough and chunky mass of black when cut.
Some varieties can splinter easily in the direction where the atomic bonds are weakened. Physically, this makes Schorl look like a black mass of splintery wood, almost like burnt bark.
This property is near impossible to imitate in other materials. Sometimes Obsidian, which is another black rock with a glassy luster, is confused with Black Tourmaline. To identify the two, cleavage is an important feature.
While Obsidian has a conchoidal fracture, that is, it is rounded, concentric, disc-like, when broken, Tourmaline has long, parallel crystal structures that splinter rather than shatter.
Observe Structural Strength
If your black rock is crumbling or powdering easily in your hands, it does not indicate that it is fake. This is very common among volcanic varieties of Schorl, especially those larger rocks, and occurs as part of large pegmatites or matrix rocks. Schorl can be very easily weakened structurally.
These pegmatite structures can be subjected to tectonic events, either during or after formation, on which Tourmaline is found.
Their effects and/or metamorphism can result in a chemical alteration to the appearance of new minerals. Even general deformation of actual fabrics, foliations, and even cleavage planes of the mineral, causing it to weaken and separate in crumbles from its parent rock.
It can happen even if your rock appears perfect on its surface. This is because crystals may be fractured and if this happens at great depth, they can be “rehealed.”
Due to fractures at great depth, vacant space is almost always immediately filled and subsequently remineralized as conditions allow. So, the crystal remains intact, yet it has been structurally weakened.
While a crumbling piece of Tourmaline is still real, it is considered low-grade, so make sure that you pay a commensurate price.
Look for Inclusions
In gemological terms, inclusion refers to any mineral that gets trapped inside another mineral at the time of formation.
These are visible in the rock, sometimes as grains of color and other times as variously sized minerals suspended in its body.
For example, an essential element in Black Tourmaline is iron, visible as red-colored inclusions on the stone’s surface.
You may sometimes notice rust collecting on your gemstone over time or at the initial purchase, which indicates the iron’s contact with moisture. Another mineral, often confused with Black Tourmaline, is Obsidian. While the color of standard inclusions in Black Tourmaline is brick-colored and rusty, Obsidian is known to have hit colored inclusions, giving it the name snowflake Obsidian.
Observe Stone Shape and Cut
Black Tourmaline is opaque, mainly with a vitreous sheen.
They are often mined from matrix rocks of quartz and other minerals such as feldspar. Such varieties of Tourmaline that terminate from a larger stone, frequently occurring alongside other minerals such as feldspar and smoky quartz, are elongated crystals but never occur in pointy pencil-like formations.
Another frequently searched question is Black Obsidian vs Black Tourmaline, to know click here.
In this article, we have summarised some of how you can identify a Black Tourmaline apart from fakes and also ascertain the quality of the stone you are buying. Often varieties of Tourmaline that powder easily leave buyers dismayed about having procured a fake. As we have suggested, this may not necessarily be the case. A rock that disintegrates easily is only a weaker variety of Tourmaline that has endured the test of several weatherings and pressure conditions in the Earth’s surface.
Such weak rock, however, should command a lower price than a Tourmaline that holds its structural integrity. More so, you must look for these cleavage planes and touch them, if possible, to understand the direction in which your rock could most easily break. The presence of cleavages is also a sign of the authenticity of a Tourmaline as it can hardly be imitated in other minerals.
You could also check that the cleavages do not appear like seams pasted onto each other, which sometimes is done to make a fake look real or a structurally weak rock to appear strong. The most common inclusion in Schorl is of the mineral iron, which may sometimes give its surface a red, rusty appearance.
This also is a good test of authenticity as many adjacent rocks like Obsidian and Onyx which are black and lend themselves to easy confusion with Black Tourmaline, occur with white-colored inclusions and not red.
Black Tourmaline is understood as a greatly healing rock. To identify and weed off fakes must also be an exercise in reflexivity about your intentions around buying this rock and leveraging its magnetic healing capacities. What are some things you learn about yourself when buying a rock? Comment and let us know.