Sodalite, cancrinite, nepheline? Canada?

A few years back I bought what was listed as sodalite from Ivigtut, Greenland from a dealer in Denmark. Upon arrival of the specimens, I started to have doubts about the identity and found some specimens of sodalite and cancrinite from Canada which looked similar. I e-mailed photos of the specimens to Claus Hedegaard who agreed that this was not Ivigtut material and that the specimens were likely sodalite and cancrinite. He speculated that they may have come from the Princess Mine in Canada and could have been brought to Denmark by the mine's owner, Paul Rasmussen, where they eventually ended up with some Ivigtut material.

I had put them away for some time but decided to catalog them today. I'm assuming the blue is indeed sodalite. There are some minor orange/yellow areas on some of the specimens but I'm not entirely convinced it's cancrinite. The matrix is grey with shiny faces and my best guess for it is nepheline.

If anyone could give me a more positive identification as to the composition and locality I'd appreciate it.



Edited 1 time(s). Last edit at 07/03/2012 08:12AM by Jenna Mast.

Jenna,

It does, indeed, look like Princess Mine material. It is possible that it is cancrinite. The combination does exist from there. You need to decide if the yellow is some sort of staining or, indeed, yellow cancrinite.

David K. Joyce

Odd stuff. The problem is that there are lots of sources of sodalite in Ontario, Canada, and worldwide, and it would take a braver man than I to claim enough knowledge to distinguish between them. Judging from the photots, I really don't think you're going to be able to pin down a locality for this one.

Eg: It could be from the Princess, or Cancrinite Hill, or Nephton, or French River, or Saint-Hilaire, Ice River, Maine, Bolivia or Africa. Can be nice pure blue cleavages, or blue cut with multi-colored veins, or various styles and combinations with brown to yellow cancrinite, or spotty aggregates running from blue on white to blue, yellow, red, white, black, etc.

In my experience, best way to deal with specimens rendered worthless by incorrect locality information is to give them away to appreciative kids, or add them to the rockpile out back. Not worth cataloging or spending any more time on.

Tim, Jenna,
The thing is that this material has those reddish streaks running through. Most or all of the localities that Tim mentioned don't usually have those reddish phases with the sodalite. In my mind, that could narrow it down to Princess Sodalite Mine(PSM) and Cancrinite Hill, which is only a km or so away from PSM. The Danish connection with Paul Rasmussen, past owner of the PSM, is also compelling.

David K. Joyce

Tim: But mystery specimens are the best kind!

I guess I'll put these in the "XRD someday" box.

The provenance certainly argues for the Princess mine as does the pinkish Hydronepheline as Dave pointed out. The blue sodalite is obvious but the cancrinite not so. The Princess cancrinite varies from a bright yellow to a dingy yellow brown. I'm not sure I see cancinite in the photo. The white could be hackmanite or if greasy, nepheline. You probably do need XRD to catch the cancrinite.