Vein quartz quarrying at 900m

In my blog on 29 January 2011 entitled “Navigational challenges on featureless plateau” I mentioned that we began our walk by following a bulldozed track that at one time serviced a quarry situated at a height of 900m (now disused), and that although I did not know what was being quarried here I hypothesized that it must have been something special to justify the challenging location.

Well, I now have the answer to what was being quarried. One of our friends, Roy, who is both a very keen mountaineer and amateur mineralogist / geologist, and actively follows our progress on-line, has provided me with the answer [thank you Roy].

Roy has sent me a copy of a scientific paper authored by R. H. S. Robertson and published in 1973 in the Scottish Journal of Science covering the analysis of the rock excavated at this quarry [Robertson73]. Robertson’s paper notes that the quarry was an investigation into the scale and viability of a vein of high-grade quartz that had been observed protruding around a stream-bed and first documented by J. G. C. Anderson in a paper in 1945 [Anderson45].

The general observation of Anderson was that the seam was very pure and uniform in quality, at least at the protruding outcrop and on the rock surface elsewhere in areas where the peak was scrapped back.

There were several reasons that this outcrop received further investigation by Robertson almost three decades later:

  • The quality of the quartz on show;
  • The perceived size of the seam (dyke-like reef);
  • The fact that it was only overburdened by peat (and not by other rock);
  • The route to get to the seam, although at 900m, began at Dalwhinnie (some 400m elevation) and the incline of the hillside to climb was reasonably modest.

However, the investigation outlined in Robertson’s paper shows that the quality of the vein quartz was not uniform with depth and samples extracted using a diamond-tipped drill showed that just below the surface (100mm deep) the quartz was “found to be no longer brilliantly white but dull grey, like mutton fat in appearance”. This reduction in quality at depth, plus the fact that bulldozed excavation of the top-layer of peat showed that the area of quartz was smaller than initially anticipated, meant that there was insufficient quantity of high-grade quartz to make extraction commercially viable.

I guess that my own hypothesis that it must have been something “special” (high-quality quartz) being quarried was sort of correct.

About Cameron Speirs

Born and brought up in the Scottish Highlands, Cameron, has been interested in outdoor pursuits since he was a wee lad. Over the last few decades he has climbed extensively in the Italian Dolomites as well as summiting the Matterhorn and several other 4000m alpine peaks. Closer to home he has spent many wonderful weekends mountaineering and biking in Snowdonia, Cairngorms, Glen Coe, Skye and Lochaber.
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4 Responses to Vein quartz quarrying at 900m

  1. Malcolm Macleod says:

    Hello to the two of you. I’m sorry I didn’t get to see you when you were passing here – things were a bit too busy: lots of my evenings involve musical rehearsals.
    I should have sent you Burns Night greetings! Even down here we managed to celebrate, though mostly not on the night itself. I went to friends in West Malvern. I know Chris Hill hosted a supper on the Friday.
    Glad to see you’re still going strong and finding a few interesting curiosities as you do.
    Very best wishes
    Malcolm

    • Cameron says:

      Hi Malcolm,
      Great to hear from you.
      Yes, we’re still going strong. It can be a bit frustrating as our progress is so dictated by the weather: sometimes we manage to get several routes done over consecutive days, and other times the weather turns poor and we can’t get out on the hills for many days. I guess that the vagaries of the weather conditions will always dictate when it is and isn’t safe for us to venture out.
      For example, we’ve just heard that the poor chap from Worcester who went missing on Ben Nevis last weekend has been found dead (yesterday). He was ill-equiped to be on any mountain in winter and appears to have succumbed to the treacherous conditions. As you can imagine, we’re choosing to “play it safe” by ensuring that the weather is favourable as we set off and that we’re carrying all of the necessary equipment to “get us out of trouble” (although accidents can happen!).
      We’ll be passing through the Midlands again in early April, and it would nice to catch up with you then.
      Please can you pass on our best wishes to Chris Hill.
      Best regards,
      Cameron (& Elaine)

  2. D Whalley says:

    Thanks for that I have been wondering about this for years!

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