Stal Cutting

The stonemasons in Tumut

I've spent the last two days in the little countryside town of Tumut, located an hour and a half a way to the west of Canberra.  It actually takes almost three hours to get there as you have to go north around the mountains to get there! Located in Tumut is a good stonemasons, and its here that we get our stalagmites cut, for fear that if we weren't getting professionals to do it, we'd muck it up! And they are very good, with some impressive machinery. As is the pace of Science we were there to get the stalagmites collected during the 2009 field-season cut, first into manageable sections, then to get a 2cm or so thick slab cut from the middle of the stal (such that the growth axis also lies in the plane of the slab, even if it moves about - it definitely helps to have a brain that works in three dimensions here) from which we do our analyses.



A box of stals, w cut three very heavy boxes worth

Our stals were cut by Jamie, who was very good at controlling the blade (1m diameter or so, they have one which must be three metres or so).  The machine is quite big, and makes the stals look small in the photograph, they're not! Bloody heavy too, its deceptively dense pure calcite.

Big cutting machine!

It takes a reasonable while to cut a stal, but we were kept busy, marking up the stals to be cut, drying cut sections, labelling them, and wrapping them in bubble-wrap so that they can survive the journey home.  Plus of course some impromptu analysis, some of the stals look very exciting, a couple are of superb quality, a few of merely good quality, and a nice aragonite one which should be interesting.  Though as ever, there were a few duds!



The first cut on Havana, one of our most promising stals, a nerve-wracking time. The stals all have names to go with their codes, to make them easier to remember and identify, this one is Havana, because it is cigar-shaped.  Or rather more cigar shaped that stals usually are!

Tumut itself is a very pretty town, located in a valley near the snowy mountains, it helps the countryside is so green at the moment but it seems like a very nice place to live, provided the jobs exist of course. And its finally, for the first time here since I arrived, actually somewhat hot, rather than warm, two degrees of which due to altitude all things being equal, but none the less really nice. Though the Chinese meal we had during the evening was suspiciously shiny.

LA marks up one of the side-offcuts

Next step is to polish and photograph the stals, XRD the bits that might be aragonite, thin-section other interesting bits, and take samples to send off to be dated.  Then maybe, just maybe, we can start analysing them!  Its a long process this, a very long process!

Removing a slab from a stal section