by Dave Hawes

A few years ago I purchased a microscope from Rolf with the view of exploring my specimens to a greater depth. Like so many good intentions the microscope languished in a cupboard for a year or two before I found the time to put it to use and realise what I had been missing out on. Not only were there minerals in different habits, but also species that I did not know I had and also ones that I did not even recognise. It was a whole new fascinating world of discovery!

After a while I thought that it could be of interest to share some of this with others. To do this required that the specimens be recorded in some format which allowed sharing, which at first did not seem to pose too much of a problem as it is not very difficult to photograph mineral specimens.

This turned out to be far from true, as the average camera will not produce acceptable images of specimens often less than 0,5 mm. Whilst dedicated microscope cameras would obviously solve the problem, in general they do not come cheap, and, as I was soon to discover, one then runs into lighting issues. As it is not the intention of this article to go into technicalities, but rather to share some hopefully interesting photographs and information on some specimens, the technical details will be left for now.

Amongst my collection I have two small specimens from the Aris quarry which is near to Windhoek in Namibia. They are small vugs in the base rock which contain villiaumite (sodium fluoride) NaF) together with some very small white spherical minerals and some sprays of a golden brown mineral.  These it turns out are ellingsenite and tuperssuatsiaite. The photographs below give an indication of the size of these specimens.


THE SPECIMENS


THE SMALL WHITE PIN HEAD SIZE
DEPOSITS OF ELLINGSENITE CAN BE SEEN


ELLINGSENITE and TUPERSSUATSIAITE
(seen along bottom)

GOLDEN BROWN BUNDLES OF
TUPERSSUATSIAITE CRYSTALS

TUPERSSUATSIAITE CRYSTALS


ELLINGSENITE CRYSTALS


A FEW DETAILS ABOUT THE MINERALS

VILLIAUMITE Na F   sodium fluoride
Named after Maxime Villiaume, a French explorer and officer in the French colonial military. Found in Brazil, Canada, Greenland, Kenya, Namibia, Russia, and Guinea (which is the type locality). Usually only found as small specimens from pink to deep carmine red. It is generally regarded as being poisonous. A search of USA poison data bases indicates that sodium fluoride was historically used in pesticides and wood preservatives. The main risks being inhalation of mist spray.
W.H.O. classify it as being obsolete and only moderately hazardous when used in commercially sold products but acutely hazardous in its pure form, so it is probably wise to wash hands after handling specimens. 

ELLINGSENITE  Na5Ca6Si18O38(OH)13·6H2O
Named after Dr Hans Vidar Ellingsen, a Norwegian mineral collector who discovered the mineral on an expedition to the Aris quarry, which is the type locality. Colour:  White.

TUPERSSUATSIAITE  Na2Fe3Si8O20(OH)2·4H2O
Named after its discovery locality, Tuperssuatsiat Bay in Greenland. Colour:  Golden yellow or golden reddish brown.