Dig Diary – Wednesday, August 17, 2016

Day Thirty-Three

Trench T structural remains.

Trench T structural remains.

Prehistoric seaweed? Maybe. But there’s definitely more art…

Jenny reveals the rich, gooey deposit in Structure Ten.

Jenny reveals the rich, gooey deposit in Structure Ten – prehistoric seaweed?

Today we have a mysterious object – a very mysterious object.

We told you recently of Jenny’s excellent efforts in showing that the paint workshop area in Structure Ten definitely related to the primary phase of use of the building.

In the same area today, Sarah and Jenny removed a secondary flagstone to discover underneath a deposit of green-tinged, gooey material, which struck some as being vaguely familiar.

The object was lying on a piece of bone and nearby was yet another small piece of wood. But it was the green gunge which attracted instant attention. Luckily, we have two green-lunge specialists on site – Sarah and geoarchaeologist Jo McKenzie.

Both identified the material as probably being unburnt seaweed – something that is intensely interesting as the survival of organic material over thousands of years is very rare.

Are new art from Structure Eleven - a partially finished 'Brodgar butterfly' or the Mark of Zorro?

The new art from Structure Eleven – a partially finished ‘Brodgar butterfly’ or the Mark of Zorro?

It also possibly accounts for the high magnesium readings which Scott Pike was getting in the area when he surveyed it with his specialised equipment.

But what could seaweed have been used for?

The proximity to the paint workshop raises the possibility of colour, or dye, or even fixative of some sort.

There are other possible suggestions, but it might be wise to wait until our plant expert, Scott Timpany, has had a closer examination of the material.

Trench X was much taken up today with BBC filming, and, in particular, a description and demonstration by Hugo to Shini (of the BBC) of his highly advanced 3D technology, which has produced some astounding three-dimensional models of the site.

By using his pole-cam and specialised software, he made a 3D model of the trench and we have high hopes that he will do the same on Sunday for Trench T, where recent amazing finds are crying out for the three-dimensional treatment.

Antonia in her makeshift 'tent' trying to get a better view of the potential spiral-decorated stone.

Antonia in her makeshift ‘tent’ trying to get a better view of the potential spiral-decorated stone.

Already in Trench T, Mark and Alette have carried out laser scanning and the hope is that this can be combined with Hugo’s 3D modelling, along with more traditional planning and drawing of the structures, to produce an image which will enable us to see many different aspects of this puzzling trench.

Nick has already made an image (pictured at the top of today’s diary) with the main features of the enormous building, which is only slowly emerging from the ground, superimposed. We will let you know what happens.

In Trench X, quite apart from the filming, closer examination of a slab located near the top of the trench, and which had clearly been reused as paving, revealed that its previous life involved decoration.

Although faint, there are extensive areas of incising and pecking and indications that some of the striations seem to swirl into spiral form.

Spiral forms are rare and famous in the Neolithic and Antonia went to extreme lengths, including hunkering under a sort of hastily constructed tent, to try and get a better look at the decoration.

The strong light of today defeated her and the stone has now been removed to safe-keeping and in preparation for further analysis.

We will also remove ourselves to safe keeping, or at least somewhere the wind doesn’t blow and the sun doesn’t shine (yes, we are never satisfied) and we will see you all tomorrow.

From the Trenches

Overview of Structure One, with Structure Twenty-One disappearing out of the top right of the trench. The central 'plaza' area is in the top left.

Overview of Structure One, with Structure Twenty-One disappearing out of the top right of the trench. The central ‘plaza’ area is in the top left.

Simon here again, taking refuge from the floor of Structure One  to regain some mental composure and sanity by the end of the afternoon . . . hopefully!

For those of you that didn’t have the pleasure of reading the first blog post I did at the start of the season, this year I have spent four weeks assisting the finds team and have now find myself digging in Structure One, where we are currently delicately excavating and sampling the clay floor deposits.

Floors are very tricky to work with. Often the stratigraphic layers are so thin and fragile that it can take time to define what is part of the deposit you are working with, as colours can merge or become obscured by lighting and weather conditions.

The grey deposit in question relates to what appears to be one of the early floor layers in Structure One, with a thin layer of grey clay laid down as a consolidating, or levelling, episode to perhaps accommodate the thicker, more robust yellow clay that we removed from above it in weeks four, five and six.

Though this is not a particularly “finds rich” deposit, we are beginning to understand and appreciate the knowledge and experience required to lay and preserve the life of a Neolithic floor, which, in itself, is something I find to be very exciting.

David's star find - a large, stone bead.

A stone bead found in the ‘central plaza’ area last month.

Further to this, many Neolithic sites (and especially those in Orkney) do occasionally have caches or deposits, either of high-status or more domestic materials, such as flint and pottery, beneath floors and hearths so, as ever, we are keeping everything crossed.

We have marked out 50cm x 50cm squares, which we are excavating systematically, one per person, before bagging and labelling the grey/white clay to be sent off for flotation and chemical analysis respectively.

The information we can gain from the further sampling of this floor layer is vast – from chemical analysis of what was being burnt, finding small artefacts (in the case of the Structure One beads) that may have been missed, or researching the sources of the clay itself, to map and understand the catchment area of the site with regards the distance and locations people at the Ness were travelling to in order to acquire all the materials needed to build and maintain the phenomenal site.

That’ll be all from me for now, but just a final word on our second open day this Sunday, August 21, with tours starting at 11am and ongoing until the guides collapse with exhaustion (final tours will start at 3.30pm)!

There will also be a “find Simon’s missing kneepad” challenge – the lucky winner of which will receive heartfelt gratitude from yours truly . . . and maybe a Kit Kat!

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