Labradorite, a captivating feldspar mineral, is widely recognized for its unique optical phenomenon known as labradorescence, an iridescent effect that creates a stunning play of colors across the stone’s surface. While labradorite itself is not geologically rare, its true rarity is nuanced and depends significantly on various factors, which dictate its quality and subsequent market value.
Geological Occurrence and General Abundance
Labradorite is a common mineral that forms primarily in mafic igneous rocks, such as basalt, gabbro, and norite, as well as in anorthosite, a rock type where it can be the most abundant mineral. It also appears in metamorphic amphibolites and as a detrital component in some sediments.
This mineral is found globally, with notable deposits in its namesake region of Labrador, Canada, where it was first identified. Significant sources of labradorite also include Finland, Norway, Russia, Madagascar, Australia, and various locations within the United States, such as Oregon, Georgia, and Montana. While the mineral itself is geographically widespread, the majority of the material extracted is not suitable for gem-quality use. The challenge lies in finding deposits that yield crystals with the specific internal structures necessary for vibrant labradorescence, making high-quality material considerably less common.
Qualities That Influence Rarity
The genuine rarity of labradorite is primarily determined by the intensity and quality of its labradorescence, an optical effect caused by light scattering within microscopic lamellar structures. Stones that exhibit a full spectrum of vibrant colors, including blue, green, yellow, orange, red, and even rare purple or pink hues, are particularly desirable. The brilliance and coverage of this color play across the stone’s surface significantly influence its rarity.
Clarity and translucence also play a role, as stones with fewer inclusions or fractures allow for a more unobstructed display of light. While some inclusions can contribute to the unique play-of-color, excessive flaws can diminish the stone’s appeal and value. Larger pieces of labradorite that maintain excellent labradorescence are notably rarer and consequently more valuable than smaller specimens.
A particularly rare and highly prized variety is Spectrolite, found exclusively in Finland. Spectrolite is renowned for its exceptionally intense and full-spectrum labradorescence, often displaying a wider range of colors than other labradorite sources. Its densely packed and aligned internal structure allows for more effective light reflection.
Market Availability and Value
The factors of quality and specific varieties directly translate into the market availability and value of labradorite. Lower-quality labradorite, which may exhibit minimal flash or only a single color, is widely available and generally affordable. These pieces often enter the market as tumbled stones or are used in mass-produced jewelry.
Conversely, high-quality, large pieces of labradorite, particularly those with strong, multi-colored labradorescence or specialized varieties like Spectrolite, are considerably harder to find. These premium stones command significantly higher prices. For instance, high-quality labradorites can be priced at $40 per carat or more, while those with rare red labradorescence can exceed $1,000 per carat.