Beryllite Crystals, w/ Tugtupite Crystals on Albite - Kvanefjeld, Greenland
Beryllite is a very rare mineral, only found in two locations: Kola, Russia and Greenland. There has been a lot of confusion about the fluorescence of this mineral. In my early days of exploration of the Ilimaussaq Complex I assumed beryllite to be fluorescent green - I had read in one book on fluorescence that was the case, and it seemed that general wisdom of the day confirmed it. But over the years we learned that most of the green fluorescing minerals we found were either chkalovite or a uranyl activated fluorescence. One of the very learned members of our team discovered that beryllite fluoresced a grayish/blue, or gray/white. With this in mind, the hunt was on. Little did I know how very rare this mineral was!
(There have been recent listings on Ebay by folks who probably visited the Ilimaussaq Complex last summer and picked up a bunch of fluorescent minerals off the ground, or from areas which we had mined out (keep in mind, this place is a "mecca" for fluorescent minerals). They see the very common green fluorescence and immediately jump to the beryllite conclusion - wrong! The Ilimaussaq Complex is a uranium complex. Uranyl salts leach out of the lujavrites and coat the rocks with a bright green fluorescence - ain't beryllite).
Over the years I kept my eye out for this mineral. The few pieces we found consisted of a white chalky coating on albite/tugtupite mixes found on Kvanefjeld. I came across this piece in my inventory and noticed the beryllite right away. While it wasn't too big to start, I decided to split it anyway on the off chance I could expose a fresh face. I was rewarded with a fine jumble of beryllite crystals, along with some beautiful, pink, glassy clear tugtupite crystals (unheard of - a faceter's dream!). Sadly, a microscope is required to really appreciate these beauties. One half is photographed here and the other half has a permanent home in my Greenland collection.
There are two galleries below. The first shows the rock under shortwave, midwave, and longwave - note how the beryllite is fluorescent under all three. The second are a few macro shots I took - natural, shortwave, and two under longwave. At the end is an animation showing the tenebrescence of the tugtupite.
The images above are macro shots of this very rare mineral. The first two are natural and shortwave, while the 2nd two show different areas under longwave.
The image above shows the color change of the tugtupite after exposure to shortwave UV (tenebrescence)