Dig Diary – Thursday, August 10, 2017
3D imaging to the rescue
Lots of interest today centred around Structure Twenty-Six, which has been painstakingly excavated by Claire and her team.
To the untrained eye it looks like a very large pile of rubble. Closer examination, however, shows curving wall lines towards the perimeter.
It is all very odd, but there is a possibility that Structure Twenty-Six has been demolished by pushing the stones from the wall heads in to the centre of the building.
One thing is clear — to draw such a huge mass of rubble on a planning board would be one of the worst jobs on site, risking eyesight, anklebones and sanity.
Even the task of balancing the planning frame on uneven rubble would have been a trial. But, luckily, we have a solution.
Regular readers will know that Jim Bright has been recording 3D images of many elements on site.
Today, Nick called him into take vertical shots of the mass of rubble, which Jim is now scaling and digitising in the comfort of the office.
Supervisor Claire will only have to plan a couple of corners of the structure and this will then be overlaid on Jim’s image to make sure that everything fits.
So, without all the problems of planning, and with a huge saving in time, we will have a highly accurate image of the structure.
Veterans with sore backs, knees and eyes will wish that this new technique could have been available 30 years ago.
Meanwhile, in Structure Twelve, Casey continued to work with the stone box she emptied last week. She is looking for a construction cut but, while doing this, noticed that some of the sides slabs are decorated and that they are each of a different type of stone.
Could there have been deliberate stone selection in the construction of the box?
She also found five hammer stones, which reflects finds in earlier seasons, and has noted that there are several more in situ.
Elsewhere in Structure Twelve, Jan and Linda are quadranting the massive northern hearth, which has a remarkable complexity of burning layers.
Surprisingly, they are not of the deep red colour (indicating firing to a considerable temperature), which archaeomagnetist Sam needs for his samples and which is present in the southern hearth of the structure.
This suggests that the two hearths may have been used with different degrees of heat and perhaps for entirely different processes.
However, the adjacent nort-west recess is full of bright red ash. Could this have been cleaned out of the nearby hearth?
Supervisor Jim has suggested that the ashes may, indeed, have come from the hearth and that they could have been placed in the recess for use as a sort of slow cooker.
It is possible that they may have been used to fire pottery as much of the later Ness Grooved Ware is undoubtedly fired at a low temperature.
Over in Trench T, Kate has been working near the drain which goes through, or perhaps around, Structure Twenty-Seven.
It was thought that this had been robbed out, but she discovered that more of the drain was visible in the section.
Supervisor Dave pushed his tape measure into the void and found that there is at least two metres of drain intact in the section, which is excellent news.
Not far away, Brooke discovered a large, red-brown, re-touched flint flake, but the find of the day came from Structure Ten’s north-eastern quadrant, where Alison and Sam uncovered a fantastic, large, red hammer-stone.
Today has been grey and bitterly cold on site and felt like a Friday. As it was not, we’ll see you tomorrow.
From the Trenches
My name is Gary Lloyd and I am starting my second year as an undergraduate student studying archaeology at UHI in Orkney. This is my first year at the Ness of Brodgar.
What is a retired, transplanted, Texan doing studying archaeology and volunteering at the Ness of Brodgar? Well, I like stone tools and rocks, and where better to study stone tools and rocks than at a Neolithic site.
I had volunteered to work processing small finds in the hope of getting the chance to see as many different kinds of stones tools as possible.
Upon reporting in my first day, I was informed that not only would I be working with the small finds coming out of the trenches, but I would also be working in the mornings with the site geologist, Martha, sorting and identifying “foreign stone”.
I was in rock-nerd heaven.
So, what are foreign stones?
In addition to the stone tools, worked stones that are used in construction of the drystone buildings, and the decorated stones, there are stones that are not found in the immediate area of the site and have no easily recognisable purpose.
Because they do not occur on site naturally, they must have been brought to the site. These are foreign stones.
Most are various kinds of sandstones of red, pink, grey, and yellow, with flecks of mica that glisten in the sun. Some are dense, igneous rocks, with microscopic crystals throughout the rock.
Most have also been heated for some unknown purpose. Did they surround the hearths? Where they used for cooking? Heated and used for warmth? Or used as potboilers?
In my three weeks on site, I expected that would have the opportunity to see and handle more stone tools than I can ever hope to find in many seasons as a digger, and I have.
I also expected to be able to get up close the worked stones and marvel at the drystone construction in the building, and I have.
What I did not expect was to be introduced to a completely new category of stones. Maybe not as glamorous as stones tools, worked stone, or decorated stones, but from my prospective equally as intriguing.