Rubies are one of the most sought-after gemstones in the world. Known for their stunning red hue, these precious stones have been symbols of love, power, and passion for centuries. When it comes to identifying a real ruby, one of the best ways to examine it is under black light. But what exactly do real rubies look like under this type of light? In this article, we will delve into the fascinating world of rubies and explore how they behave under black light.
Understanding how rubies respond to ultraviolet (UV) light can help you distinguish between a genuine ruby and a synthetic or treated stone. Let’s dive in and learn everything there is to know about rubies and black light.
What is Black Light?
Black light, or ultraviolet (UV) light, is a type of light that has a wavelength longer than visible light but shorter than X-rays. It’s not visible to the human eye, but certain materials, including rubies, will fluoresce when exposed to UV light. Black light is commonly used in various industries, including gemology, to test the authenticity and quality of gemstones.
When a ruby is placed under black light, it may emit a visible glow, and the color and intensity of that glow can reveal a lot about the stone’s authenticity and origin. The ability of rubies to fluoresce under black light is one of the key characteristics that jewelers and gemologists use for identification purposes.
Fluorescence in Rubies
Fluorescence is the emission of light by a substance that has absorbed light or other electromagnetic radiation. Many rubies display fluorescence when exposed to UV light, and the color of the fluorescence can vary depending on the chemical composition of the ruby.
Real rubies typically show a red or orangish-red glow when exposed to black light. This glow is a result of the trace amounts of chromium that are present in rubies, which are responsible for giving them their distinctive red color. The higher the chromium content in the ruby, the more intense the fluorescence can be.
Not all rubies fluoresce under black light, but the majority of high-quality rubies do. However, it’s important to note that the absence of fluorescence does not automatically mean the ruby is fake. Some rubies, particularly those that are treated or synthetic, may not exhibit fluorescence under UV light.
Natural vs. Synthetic Rubies Under Black Light
One of the main differences between natural and synthetic rubies is how they react to black light. Natural rubies, which form deep within the Earth’s crust over millions of years, tend to have more intense fluorescence. On the other hand, synthetic rubies, which are created in a laboratory setting, may not display fluorescence or may fluoresce in a way that differs from natural rubies.
Real rubies often display a strong, vibrant red or pinkish-red glow when exposed to UV light. The fluorescence may be more subtle or brighter, depending on the specific ruby. Synthetic rubies, however, tend to show a weaker or different kind of fluorescence that is not typical of natural rubies.
The best way to distinguish between a natural and synthetic ruby under black light is to examine the intensity and color of the fluorescence. A real ruby typically produces a red or orange-red glow, whereas a synthetic ruby might show a duller or different colored glow, such as a blue or purple hue.
The Role of Chromium in Fluorescence
The chemical element chromium plays a significant role in the coloration and fluorescence of rubies. It is the presence of chromium that gives rubies their characteristic red color. When exposed to UV light, chromium causes rubies to glow, which is why rubies with higher levels of chromium tend to exhibit more intense fluorescence.
Rubies that have a higher chromium content will generally produce a brighter, more vivid glow under black light. In contrast, rubies with less chromium may show a duller or weaker fluorescence. Some rubies, especially those that are lower in chromium or have been treated, may not fluoresce at all under black light.
The intensity of the glow also depends on other factors, such as the stone’s size, quality, and treatment. While natural rubies typically have more vibrant fluorescence, some treated or synthetic rubies may show only faint or no fluorescence at all.
Differences in Fluorescence Based on Origin
The origin of a ruby can also affect how it reacts under black light. Rubies from different regions of the world often have unique characteristics when exposed to UV light.
For example:
Burmese Rubies: Rubies from Myanmar (formerly Burma) are known for their deep red hue and high-quality fluorescence. These rubies often emit a bright red glow under black light due to their high chromium content.
Thai Rubies: Thai rubies, which are generally lighter in color, may also fluoresce under black light but tend to have a more subtle glow compared to Burmese rubies.
African Rubies: Rubies from Africa, particularly those from Mozambique and Kenya, often show a reddish fluorescence under UV light, but the intensity can vary widely depending on the stone’s chromium content.
Understanding the specific fluorescence characteristics of rubies from different regions can help jewelers and collectors identify their origins.
Ruby Treatments and Their Effect on Black Light Fluorescence
Many rubies undergo various treatments to enhance their color and clarity. These treatments can also impact how a ruby behaves under black light. The two most common treatments are heating and fracture filling.
Heated Rubies: Most rubies on the market are heat-treated to improve their color and clarity. Heating can enhance the fluorescence of rubies, making their glow more pronounced under black light. However, heating may not always cause the same kind of fluorescence as naturally occurring rubies, and some heat-treated rubies may have a less intense or different-colored glow.
Fracture-Filled Rubies: Fracture filling is a treatment used to improve the appearance of rubies with surface cracks or inclusions. This treatment often involves filling the cracks with a glass-like substance. Rubies with this treatment can sometimes show a different kind of fluorescence under black light, depending on the composition of the filling material. The fluorescence in these rubies might appear more subdued or inconsistent, and it may be harder to detect.
It’s important to be aware that treatments can sometimes obscure the natural fluorescence of a ruby, making it more challenging to accurately assess the stone under black light.
How to Test Rubies Under Black Light
Testing rubies under black light is a simple process that can provide valuable information about the stone’s authenticity and quality.
To perform a black light test, you will need the following:
- A black light or UV lamp
- A dark environment where you can observe the ruby under UV light
- A clean ruby (free from oils, dirt, or other contaminants)
Here’s how to conduct the test:
- Turn off all other light sources in the room to ensure the black light test is effective.
- Place the ruby under the black light and observe its fluorescence.
- Note the color, intensity, and consistency of the glow.
- Compare the fluorescence with known examples of natural rubies, keeping in mind the factors that can affect fluorescence, such as origin, treatment, and chromium content.
If the ruby exhibits a bright red or orange-red glow, it is likely a natural ruby with high chromium content. If the ruby shows no fluorescence or a different kind of glow, it may be synthetic or treated.
Conclusion
Understanding how rubies behave under black light is an essential tool for identifying genuine rubies and distinguishing them from synthetics or treated stones. Natural rubies typically fluoresce with a vibrant red or orange-red glow due to the presence of chromium. While not all rubies will fluoresce, those that do provide valuable insight into their authenticity and origin.
Whether you are a jeweler, collector, or enthusiast, knowing how to examine rubies under black light can help you make informed decisions when buying or selling these precious gemstones. Always consider the color, intensity, and origin of the fluorescence to get the most accurate results.
Related topic:
- Are Emeralds Rarer Than Rubies?
- Natural Ruby vs Artificial Ruby: What Is the Difference?
- Why Are Some Rubies so Cheap
