Happy New Year Crystal Lovers!
We’re kicking off our first gemstone blog of 2020 talking about the geology of a truly fantastic gemstone. That’s right everyone, Labradorite is the beauty we’re discussing this week.
Labradorite is a sodium-rich Plagioclase Feldspar found in the main three classes of rocks. It often occurs as a primary mineral in rocks such as basalt and gabbro. The base color of this crystal is a dark, smoky, gray. What makes this one of the coolest crystals on the planet is that it produces an effect called Labradorescence.
Labradorescence is the sheen of rainbow that bounces of Labradorite when you move it around. This iridescence is unique to labradorite in the mineral kingdom, and it is the presence of this phenomenon that makes Labradorite so appreciated.
The colors range from a common blue and green to the less common purple, red, orange, and rare golden colors.
On the MOHS Scale, labradorite lands at a hardness of 6 – 6.5 and has 2 directions of cleavage that intersect. So, if you happen to drop a chunk of it, it will break in 2 perfect pieces due to the crystalline structure. On hard impact however, this stone is likely to shatter. This two-directional intersecting growth pattern is referred to as “Twinning”.
Twinning occurs when there are two crystals that share a symmetrical growth and is often how labradorite is correctly identified. It’s the only crystal that produces that beautiful rainbow sheen Labradorite is classically known for. Twinning is such a cool process that we can’t possibly do enough justice in this short blog post, so if you would like to get your nerdy-on; check out this article here.
Not all pieces of Labradorite have this namesake rainbow sheen we swoon over in the gem community. Labradorite is the only mineral in the Plagioclase family that exhibits that rainbow sheen so it can require a bit of testing to classify the mineral properly when this isn’t obviously present. There are other cool factors to consider when hunting for the perfect specimen of Labradorite too.
Labradorite is not a stone that is “mass produced” so the jewelry that you do find on the market is often custom and unique. No two stones will look identical, even if the setting does. Some labradorite won’t have the rainbow sheen to them but will instead present an effect called Adventurescence or the Schiller Effect which is an optical reflection within the stone that put plainly, looks like glitter. This effect can be most clearly seen in crystals such as Sunstone and Aventurine.
Labradorite is a beautiful stone to put into jewelry but for those that do a significant amount of work with their hands, especially if that involves bumping into hard surfaces, this stone would be better suited as a pocket stone or in the form of a pendant to wear as a necklace.
For casual wear however this stone is perfectly fine to wear in ring form. Be aware that it is weaker than quartz so anything stronger than a 6 on the MOHS scale will scratch it. Carrying it around in a pouch with quartz, is still safer than carrying around a piece of fluorite or apatite with quartz so don’t let the MOHS rating scare you off from working with this stone daily.
Labradorite was discovered in 1770 by a Moravian missionary in Labrador, Canada. This said, Labradorite can be found in Canada, Finland, Madagascar, India, Russia, and Oregon. There are levels of “quality” to Labradorite. As we mentioned above, Labradorite that has that classic Labradorescence is the most sought after.
The brightest Labradorescence specimens tend to come from Finland and are called Spectrolite. Spectrolite hosts a much richer range and depth of colors. Traditional Labradorite has the colors of blue, gray, or green and that’s about it. This range and depth are why finding a piece of Labradorite with Purple, Red, Orange, or Gold are so rare and are priced accordingly.
Labradorite found in the continental United States is a transparent type that is marketed as Oregon Sunstone. Additionally, there is another type called Larvikite. Larvikite is an igneous rock found in Norway, it’s typically used as building material but can be found as gemstones and palm stones on the open market.
The primary difference between what qualifies as “gemstone quality” and not is the level of Labradorescence and density for this mineral.
That’s it for the Geology of this amazing gemstone. Make sure you bookmark our blog and check back at the end of the week when we get metaphysical with Labradorite!