Labradorite is a feldspar mineral known for its optical phenomenon called labradorescence (also known as the schiller effect). This property causes a play of iridescent colors, with flashes of blue, green, yellow, orange, and occasionally red across its surface. Its striking appearance makes it a popular choice in jewelry and decorative arts. Its allure stems from this inner fire, which seems to dance and shift with every change in viewing angle.
Geological Formation and Environments
Labradorite originates as an igneous rock-forming mineral, crystallizing from molten magma deep within the Earth’s crust. It is found within mafic igneous rocks, such as basalt, gabbro, and anorthosite formations. The slow cooling process of this magma allows the mineral to develop its characteristic structure.
Labradorescence is a result of microscopic exsolution lamellae within the stone’s internal structure. These thin, parallel layers of varying mineral compositions scatter and interfere with light as it passes through the stone. This interaction causes the light to separate into spectral colors, creating the iridescence.
Key Global Deposit Locations
Labradorite is found in various regions globally, with the most famous deposits in Labrador, Canada, where the mineral was first identified. This region produces high-quality specimens with vibrant labradorescence. Madagascar is another source, often yielding large pieces with good color and clarity. Finland is known for its vibrant variety, Spectrolite, which exhibits a full spectrum of colors.
Other locations for labradorite include Norway, Russia, and Australia. In the United States, deposits are found in areas like Oregon, where a variety of labradorite known as sunstone is mined. These diverse geological settings contribute to subtle variations in the stone’s appearance and optical characteristics.
Commercial Acquisition Channels
Labradorite is available through commercial channels for collectors and those seeking finished pieces. Jewelry stores offer a range of items, from rings and pendants to earrings and bracelets. These establishments provide polished and set labradorite.
For individuals interested in raw stones, polished cabochons, or larger specimens, lapidary shops and gem and mineral shows are good resources. These venues feature a selection of unmounted stones for custom designs or collecting. Online retailers specializing in crystals, gems, and minerals provide another avenue for purchasing labradorite, with options from rough to cut. Artisan markets also offer unique, handmade jewelry incorporating labradorite. When purchasing, seek reputable sellers who can provide information about the stone’s origin and quality.
Recognizing Authentic Labradorite
Identifying genuine labradorite relies on observing its optical phenomenon, labradorescence. Authentic labradorite displays an iridescent flash of colors that shifts as the stone is moved. This internal play of light is the primary indicator of its authenticity.
The base color of labradorite ranges from dark gray to black or greenish-gray when the iridescent flash is not active. The stone is opaque to translucent, with transparent specimens being rare. Labradorite has a Mohs hardness of 6 to 6.5, making it resistant to scratches from many common materials but susceptible to damage from harder substances. Imitations, such as glass or other treated stones, lack the distinctive internal flash and natural inclusions found in genuine labradorite.