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Cryolite is a mineral of aluminum (Na$_3$AlF$_6$). The only known natural deposit was found in Ivittuut, Greenland. It was mined from 1854 to 1987 and yielded 3.7 Mt of Cryolite ore.

Basically my question is, why is this the only cryolite deposit known? What is the origin of it and why didn't any more form?

There are a lot of similar islands in the arctic: Canadian islands, Russian islands, Scandinavia and Svalbard, etc. Do geologists believe other Cryolite deposits are out there, just not discovered yet?

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Ivigtut Cryolite deposit, Ivittuut (Ivigtut), Arsuk Fjord, Sermersooq, Greenland deposit is the first and largest occurrence of Cryolite but it is not the only location to report Cryolite.

Some of these other locations listed below have produced collectible specimens but cryolite does not occur in large enough quantities to be mined.

Other important locations are: Reference (I have seen specimens from these locations)

  • ST PETERS DOME PEGMATITE PROSPECT, Pikes Peak Colorado
  • Francon Quarry Mt St Hilaire, QUEBEC

(other listed locations, Reference)

  • MONZONITE GROUP, Gunnison County Colorado
  • FANNY GOUGE MINE, Yancey Co. North Carolina
  • BARINGER HILL MINE, Llano, Texas
  • MC GUIRE PIT Marathon Wisconsin.
  • Also reported from near Miass, Russia.

I also suspect there are other Canadian locations but Canada publishes less mineral data than the United States does.

Cryolite occurs in syenite vein deposits (igneous rock which is quartz deficient) which had abundant amounts of fluorine.

There are 13 other known mineral specimens that contain primarily: Na, Al, F. Cryolite is the most common mineral, due entirely to the Ivigtut deposit. The geologic conditions at the Ivigtut deposit led to deposition of cryolite instead of an other mineral phase containing Na, Al, and F.

I believe additional deposits with cryolite may be found in the future but the Greenland deposit is likely to remain the first and most important deposit. There are a handful of completely unique ore deposits on earth, Ivigtut Cryolite deposit is one of them.

See zincite from Franklin New Jersey as another example where a specific mineral was only ever commerically mined from a singular location.

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  • $\begingroup$ Barringer peaked my interest, so I've just looked it up in "Texas Through Time" by Thomas Ewing (publ end of 2016). This doesn't mention cryolite, but the Barringer Hill pegmatite is mentioned. Discovered 1887. Mined for REEs, especially Gadolinite. Described as a "rich" deposit (for REEs). Now submerged beneath Lake Buchanan. $\endgroup$ – winwaed Feb 14 '17 at 18:03

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