Labradorite is a feldspar mineral known for its striking optical display, making it a popular choice for jewelry and decorative pieces. Because this stone is highly valued for its unique color-play, the market frequently sees fakes and imitations passed off as genuine labradorite. Understanding the specific characteristics of the real stone is the best defense against purchasing a counterfeit piece.
The Signature Feature of Labradorite
The defining characteristic of genuine labradorite is an internal metallic luster known as labradorescence. This optical effect is not a surface color but a dynamic sheen of iridescent color that flashes across the stone. The colors, typically vibrant blue, green, and occasionally yellow or orange, appear to come from deep within the mineral itself.
This phenomenon is caused by the diffraction of light off microscopic layers within the mineral. These layers, known as exsolution lamellae, are thin, parallel planes of different chemical compositions. When light enters the stone, it interacts with these internal structures, scattering and reflecting light to produce the spectral colors.
The resulting flash is highly directional, meaning the color appears only when the stone is held at a specific angle relative to the light source. As you slowly rotate a piece of genuine labradorite, the vibrant color will abruptly appear, shift, and then disappear again, leaving behind the stone’s natural gray or dark base color. This dynamic, angle-dependent flash is the standard against which all imitations must be measured.
Materials Used to Create Fakes
Imitations of labradorite attempt to replicate the signature color flash but generally fail to capture the depth and shifting quality of the natural stone. One common category of fake involves glass and synthetic materials. These often include dyed or treated glass that might possess a shallow, uniform sheen that lacks the dynamic color-play of labradorescence.
Glass-based fakes sometimes contain glitter or a consistent holographic film distributed throughout, giving them a superficial sparkle visible from almost every angle. Unlike the natural stone, the color often appears too vivid or neon. The internal structure may also show telltale signs like small air bubbles.
Another common imitation involves plastics and resins, often seen in inexpensive jewelry. These fakes are typically created using mixtures of polymer clay or resin combined with mica powders or iridescent films to simulate the flash. While they can look convincing in photographs, they feel noticeably light and sometimes warm to the touch, betraying their plastic composition. The color-play on these pieces often looks like a static, painted-on coating rather than a genuine three-dimensional optical effect.
Simple Tests for Authentication
The most effective way to authenticate a piece of labradorite is by closely observing its interaction with light. Hold the stone under a bright, focused light source and slowly tilt it, watching for the labradorescence. A genuine stone’s flash will appear suddenly and intensely, moving across the surface, and then vanish entirely when the stone is tilted slightly further. A fake will often show a static color or a uniform sparkle that remains visible across all angles, much like a piece of holographic foil.
A tactile examination can quickly rule out many plastic or glass imitations. Genuine labradorite is a dense mineral, meaning it should feel noticeably heavy for its size. Natural stones are poor thermal conductors, so a genuine piece will feel cool to the touch. Plastic or resin fakes will feel room temperature or even slightly warm right away.
A visual inspection of the stone’s surface can reveal manufacturing flaws common in imitations. Look closely for air bubbles, which are a strong indicator of glass or resin construction. Natural labradorite is rarely flawless and may contain minor inclusions or internal fractures, while a piece that appears suspiciously perfect and uniform might be synthetic. The mineral has a moderate hardness on the Mohs scale.
The final check involves examining the stone when no flash is present. The base color of real labradorite is typically a dark gray, black, or grayish-white. If the stone is overly transparent or if the colors appear unnaturally bright or uniform when the flash is absent, it may be a dyed or treated imitation.