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Real vs. Fake Obsidian Stone: Check These 8 Key Differences

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Obsidian fakes can be remarkably deceptive, often requiring time, patience, and specialized tools to distinguish them from their natural counterparts. Despite obsidian’s abundant availability worldwide, counterfeit gemstones are still prevalent.

However, real and fake obsidian can be differentiated through eight key factors:

  • Color: Real obsidian typically exhibits dark hues.
  • Texture: It ranges from translucent to opaque.
  • Density: Natural obsidian is notably dense.
  • Hardness: It possesses a certain level of hardness.
  • Translucency: As mentioned, translucency varies.
  • Bubble Formation: Real obsidian may contain distinct bubble patterns.
  • Hot Needle and UV Light Reaction: Natural obsidian doesn’t react to UV light and specifically responds to a hot needle test.
  • Form of Occurrence: Authentic obsidian never forms crystals.

Interestingly, “Dragonglass” from the popular TV series Game of Thrones is actually obsidian! Its prized properties within the show mirror the real-world value placed on this natural glass.

Identifying real obsidian can be challenging due to its similarity to other types of glass. However, understanding these key differences allows you to better navigate the obsidian world and appreciate its unique qualities.

Real vs. Fake Obsidian Stone
Real vs. Fake Obsidian Stone

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How to Tell if Obsidian Stone is Real

Real obsidian is commonly known as a black-colored, translucent, or opaque stone with very sharp edges and characteristic conchoidal (shell-like) fracture. Obsidian was known to ancient people as a hard, sharp, and durable material and used as knife blades, arrows- and spearheads.

To tell if an obsidian stone is real, check the intensity of color and translucency and examine the stone attentively under magnification. Next, observe the characteristics of texture and gas bubble inclusions. Finally, the sample was checked with a hot needle to exclude substituents made of plastic.

Obsidian’s distinguishing features are confined to its geological formation process. Obsidian is a natural glass that formed as a result of rapid lava solidification on the surface. Obsidian usually has a rhyolitic composition. It is composed of more than 70 percent silica and is low in volatile content.

Formation on the surface led to air bubbles trapped in obsidian during solidification. The bubbles can be of elongated forms that follow the direction of lava flows.

Obsidian is neither a rock nor a mineral. It is considered to be a mineraloid as it has no crystalline structure. It cannot be classified as a rock as there is an almost total absence of sizable mineral crystals within the glass matrix. Because of rapid solidification, crystals have no time to grow in a lava flow.

Even composed of mostly silica, obsidian is softer than quartz and any of its varieties. Obsidian typical hardness is 5 to 5.5 on the mineral hardness scale.

In contrast, quartz (crystallized silicon dioxide) has a hardness of 7.0. This feature allows distinguishing real obsidian from quartz, chalcedony, and their numerous varieties.

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What Does Real Obsidian Stone Look Like

Real obsidian generally looks dark (black, brown, dark green, and dark blue colors). It is opaque or translucent, which means it doesn’t transmit light through. Textures of real obsidian are naturally uneven. Bubbles in real obsidian look elongated and generally follow the same direction.

Can Obsidian be Faked?

Even though it is readily available, obsidian can still be faked. Obsidian fakes are represented mainly by glass and plastic because glass has very similar physical properties to real obsidian. Plastic, in turn, is a good imitation of textures, especially for snowflake obsidian. 

What Can Be Mistaken for Obsidian

The most common unnatural obsidian substituents are glass and plastic. However, natural materials like black onyx, jet, jasper, and morion (black quartz) can sometimes be mistaken for obsidian. They all have typical characteristics that can help differentiate them from real obsidian.

How to Spot Fake Obsidian Stone

Distinguishing between fake and natural obsidian is very challenging. The main reason is that the most common obsidian fake is glass. Natural obsidian is also glass but created by nature.

That is why setting apart two types of glasses is very complicated. Even for gem professionals, it is hard to tell apart fake and real obsidian without any additional gemological tools.

To spot fake obsidian, check the saturation of color. It should not be bright, translucency (fakes will be transparent), hardness (hardness of fakes is lower), and density (real obsidian feels harder and denser). The texture of fakes is too even and smooth. Fakes can be molten by a hot needle and glow under UV.

TIP: The real obsidian is a naturally occurring volcanic glass. And some of the real obsidian varieties can be quite expensive. Find out more about the value of obsidian in the article below:
5 Crucial Factors of Obsidian Value: What’s Obsidian Worth?

Main Differences Between Real and Fake Obsidian

Main Differences Between Real and Fake Obsidian
Main Differences Between Real and Fake Obsidian

The main difference between real and fake obsidian is color and translucency. Real obsidian will now be bright-colored and perfectly translucent.

Also, because of specific geological formations, real obsidian will have elongated gas bubbles, while fake has rouned once. Additional hot needle and UV test let spot plastic fakes.

Characteristic propertyReal obsidianFake obsidian
Hardness5.5 on the Mohs scale. Real obsidian can be scratched by a knife and a piece of glass. Scratch is uneven, and the out-of-scratch material of real obsidian is white and chalk-like.Fake obsidian made of plastics can be scratched by a knife and a piece of glass. The scratch is even, and the out-of-scratch material doesn’t break apart.
Bubbles’ appearance under magnificationAll bubbles have an elongated appearance in one direction, indicating lava flow.Bubbles in man-made glass are commonly round.
Density Real obsidian feels heavier and denser in comparison with man-made glasses.Feels light and less dense than natural stone.
ColorThe colors of real obsidian are dark and dull. However, they are never too vividly saturated and have an admixture of brownish and grayish stains.The colors of fake obsidian can be vivid blue, bright green, and intense red without any admixture of gray and brown hues.
TranslucencyReal obsidian is commonly opaque and translucent.Transparent stones are a sign of fake obsidian.
TextureNatural obsidian has never even repetitive textures.Fake snowflake obsidian can be spotted due to repetitive textures.
Glow under UV lightReal obsidian is inert and doesn’t glow under UV. Artificial glasses and translucent plastics can glow under UV in chalky-bluish colors.
Hot needle testNo interaction with a hot needle.Plastic substituents for obsidian will produce a burnt plastic odor.
Differences Between Real and Fake Obsidian

TIP: Acquiring a piece of obsidian that needs to be cut and polished can be quite stressful if you have never done it before. Find out more about cutting and polishing obsidian in the article below:
How to Cut & Polish Obsidian: Follow These 7 Simple Steps

Differences for Special Obsidian Varieties

When people hear the word obsidian, black-colored material comes to their minds. But there are also some very intriguing obsidian varieties that can surprise them.

For example, rainbow obsidian is a relatively new material with a phenomenal appearance. The unusual rainbow sheen attracted the attention of many people, including fake manufacturers.

There are several obsidian varieties: black, snowflake, green, blue, and rainbow. They never occur in highly saturated hues and eye-clean transparency. Rainbow obsidian’s sheen is displayed on a translucent to an opaque dark background. Snowflake obsidian texture is never repetitive, not even mathematically.

Let’s briefly describe the most common obsidian varieties. Their distinguishing features you can check in the table below.

  • Black obsidian is the most common and abundant material. Microscopic impurities of magnetite, hornblende, pyroxene, plagioclase, and biotite produce the jet-black varieties of obsidian.
  • Snowflake obsidian is a very appealing material where white or gray cristobalite crystals contrast on a black glassy obsidian background and resemble snowflakes. 
  • Green and blue obsidian’s rare colors result from microscopic crystals of various types of feldspars.
  • Rainbow obsidian is the most valuable variety. Its colorful phenomenon is explained by oriented nanorods of hedenbergite via thin-film interference (Ma, C. et al., 2001).

The table below highlights unique properties typical for particular obsidian varieties. It can help to set apart real and fake stones:

Obsidian varietyReal obsidianFake obsidian
BlackReal black obsidian is never perfect. It has impurities and bubbles of elongated forms.Fakes are too even and perfect. If there are any bubbles, they are of round form.
SnowflakeThe color of real green obsidian is never too vivid and saturated. Real green obsidian is rather black obsidian with a green tint rather than emerald-like colors.Fake snow obsidian can be spotted due to the exact size of “snowflakes” and their uniform and repetitive distribution.
GreenReal rainbow obsidian is black or dark gray obsidian with a rainbow sheen. It is not bright and transparent. The colors of fake green obsidian are too bright and saturated.
BlueReal blue obsidian is dark and dull with a blue overtone.Fake blue obsidian is too bright and vivid without gray and black hues.
RainbowReal rainbow obsidian is black or dark-gray obsidian with a rainbow sheen. It is not bright and transparent. Fake rainbow obsidian is too bright and saturated. It can be eye-clean and transparent.
Real vs. Fake Obsidian: Differences for Special Obsidian Varieties

TIP: Rock color is the first property we pay attention to. Even if the rock is heterogeneous, we can still determine the general color of the rock in front of us. Find out more in the article below:
Rock Colors: What Determines Color & Why Different Colors

Conclusion

Real obsidian is a challenging gemstone to identify and differentiate from fakes without additional equipment testing. This is especially true if an obsidian sample occurs in a tumbled state or is set into jewelry. 

Obsidian fakes are represented by two groups of substances. They are;

  • Natural materials are represented by black onyx, jet, jasper, and morion (black quartz).
  • Man-made materials are glass and plastic-based materials.

To tell apart real and fake obsidian apart, pay attention to the following properties:

  1. Color.
  2. Transparency
  3. Density 
  4. Hardness
  5. Texture
  6. The form of trapped bubbles.

Additionally, you can take an easy test on

  1. Hot needle test reaction
  2. UV light reaction

They allow the separation of genuine obsidian from plastic-based imitations.

TIP: Obsidian is among the most prized rocks that all rockhounds want to have in their collections. But where to find it? Check out the complete guide in the article below:
Finding Obsidian: 6 Best Locations Near Me (United States)