Tourmaline is found in different parts of the world and comes in various types including rubellite, indicolite, chrome tourmaline, and Paraiba tourmaline. With its colorful allure, some wonder if tourmaline glows under UV light like some other gems. Here's a look at the fluorescence traits of this stunning stone.
What Makes Gemstones Glow Under UV?
Ultraviolet light falls just outside of the visible light spectrum. Special minerals in some gemstones absorb this non-visible UV light and then emit it back as visible light, making the gems appear to glow. This is called fluorescence. The glow effect can make gems seem more brilliant. Not all stones exhibit fluorescence, and those that do can glow in different colors. Some of the most famous UV-responsive gems include diamonds, which often glow blue, and amber, which commonly fluoresces greenish-yellow.
Does Natural Tourmaline Fluoresce?
Natural tourmaline does not normally fluoresce under ultraviolet light. Most tourmaline specimens remain inert under UV rays. This includes commonly seen tourmaline types like rubellite (pink to red), indicolite (blue), chrome tourmaline (green), and the prized Paraiba tourmaline (neon blue-green). The lack of fluorescence is one of the ways gemologists can identify tourmaline and separate it from imitations.
While most natural tourmaline won't glow under UV light, there are a few rare exceptions. Some unique tourmaline specimens contain trace elements like manganese that enable a slight fluorescence. These rare glowing tourmalines might show a weak red or orangey reaction under UV lamps. However, the effect is typically very dim compared to strongly fluorescent gems. Most tourmaline lovers should not expect their stones to light up under UV.
What About Treated Tourmaline?
Some tourmaline is treated to enhance the color. The treatments can involve heat, radiation, or stable diffusion to transform light-colored tourmaline into deeper red, green, or blue shades. Treated tourmalines usually do not glow any more than their natural counterparts. However, some heavily included tourmalines are impregnated with epoxy or oil to hide flaws. These treated, fracture-filled stones may fluoresce brightly under UV light, unlike natural tourmaline. The vivid glow is a telltale sign that the tourmaline has been impregnated.
While fluorescence can be useful for separating natural and treated gems, the lack of UV responsiveness should not be taken as proof of a tourmaline's natural origins. Other testing would be needed to confirm a tourmaline is untreated. But generally, if you shine a UV light on your tourmaline jewelry and it glows unusually bright, it is likely treated. Natural tourmaline typically remains inert.
A Stone Admired for Its True Colors
Part of tourmaline's appeal lies in its pure, unenhanced colors. This gem gives us vibrant pinks, blues, and greens just as nature intended. While fluorescence can add intrigue to some gems, tourmaline stands out in its own right without any special UV tricks. Natural tourmaline gets its captivating hues from trace elements like manganese, iron, and copper. We simply admire these stones for their true colors under normal light. And that's perhaps how it should be for this beloved gem.
