Many people love the incredible rainbow flashes that Labradorite crystals offer (it's one of my all-time favourite crystals). It is named after Labrador in Canada, where it was first discovered. It has since been found all over the world, in places such as Madagascar, Australia and the Adirondack mountains in America, a place we in fact went rockhounding for Labradorite last year. It is most commonly seen gold, green and blue colours, but can have a wider play of colours, for example rarer purples, reds, pinks and oranges. High quality Labradorite deposits have recently been found in Madagascar.
Spectrolite is a very special, gem quality variety of Labradorite that can show a full spectrum of rainbow colours that can only be found in Finland. This is because Spectrolite is a trade name that only applies to the specific variety mined in Finland, it was named by a Finnish geologist and you can still visit the Ylamaa quarry in Finland where it is mined. It also has a very dark, black base, and is considered a semi precious gem, whereas Labradorite generally is not. The lines on Spectrolite that break up the colours also tend to be much harsher, whereas the colours in Labradorite blend into each other much more.
The name Spectrolite is often used by some sellers to describe Labradorite that shows off a wide range of colours, however these are not true Spectrolite, just high quality Labradorite. It's also a little cheeky as true Spectrolite fetches a higher price than normal Labradorite due to it's rarity and quality. So if it's true Spectrolite you want, make sure that the Spectrolite you buy is actually from Finland. If it's not, then it's simply not true Spectrolite (just high grade Labradorite, probably from Madagascar). Don't pay a premium just because a seller labels it as Spectrolite - choose your Labradorite on your attraction to it, as Madagascan Labradorite still displays a massive variety of colours for a much lower price. Our personal collection contains a huge amount of Labradorite, and one very special piece of Spectrolite - it is a stunning variety and worth having, but it's hard to find genuine pieces and it's quite pricey!
Here are some images of Labradorite, notice the wide variety of colours and how the contrast is a lot softer:
Here are some images of Spectrolite from Finland, notice how the edges of colour look much different to the Labradorite:
Images of Spectrolite courtesy of Etsy: Lapicary and unknown; Flickr: Jessa and Mark Anderson