| This post is prompted by a first visit to Wessex Archaeology at their Salisbury premises. The A556 Knutsford to Bowden Improvement scheme (begun in 2014 and due to complete in the winter of 2016-17) involves creating 7.5 km of new dual carriageway. As part of an assessment of the environmental impact to our cultural heritage (the prehistoric and roman remains), Wessex Archaeology was asked to make the necessary investigations. The material I had from the tank was from bulk samples from Knutsford. This material is stored in tubs (see photo) the samples can vary from a few litres to (usually) up to 40 litres in size. There is a large amount of waste material! The sample of Knutsford residue I was given to take away is fine pigmented residue left in the base of the flotation tank after the coarse materials and organic matter/ charred matter- molluscs etc have settled or floated off. The bulk samples collected by all the regional offices are processed in Salisbury. |  Monoliths in storage. I have yet to work with the monoliths I have been given.  Tubs containing bulk samples from across the country. |
2. Sarah Wyles (Senior Environmental Archaeologist in the Geoservices team) identified some unwanted monoliths that are now waiting in my studio. The topic of another blog no doubt.
This will of course be a vertical sample. Not the usual horizontal one I usually access. The material will have been systematically analysed and dated. Site specificity is important to me. The data available takes this to a new level. Monoliths can come from a variety of features, such as ditches and palaeochannels not necessarily just trial trenching and are a way of being able to look closely at the depositional processes going on in that feature. Environmental Archaeologists can also subsample these to look for material such as pollen and organic material for C14 dating as well as foraminifera and ostracods (microscopic organisms that are indicators of water salinity and habitats). The samples from monoliths are generally fairly small, are processed in sieves in the sink and produce little waste material. There are often monoliths surplus to requirement however...again a useful source?
This will of course be a vertical sample. Not the usual horizontal one I usually access. The material will have been systematically analysed and dated. Site specificity is important to me. The data available takes this to a new level. Monoliths can come from a variety of features, such as ditches and palaeochannels not necessarily just trial trenching and are a way of being able to look closely at the depositional processes going on in that feature. Environmental Archaeologists can also subsample these to look for material such as pollen and organic material for C14 dating as well as foraminifera and ostracods (microscopic organisms that are indicators of water salinity and habitats). The samples from monoliths are generally fairly small, are processed in sieves in the sink and produce little waste material. There are often monoliths surplus to requirement however...again a useful source?
| Possible lines of enquiry prompted by the visit: 1. The pigmented residue (that may well interest me in my own work) is a natural waste product that builds up in the base of the cylinders and is empted out into an underground disposal tank. The dark colour of this particular sample is due to charred particles within it. There is a large amount of waste material generated on the site.  Area dedicated to the sorting, sieving and separation of samples. Flotation tank in the foreground. |  taking a scoop of the Knutsford residue from the flotation tank. |
 | 3. Nicki Mulhall (Environmental Archaeologist) determines the texture of soils and sediments by finger testing and sight. I get to know my materials through touch and sight too- but the information I glean is related to the way I might engage with it directly (I need to understand it so that I might use it to form a pigment/ communicate an approximation of its colour or surface quality through a paint medium). I do not analyse or classify it (so that it may provide information that can contribute to an investigation of place) or situate it clearly within a recognised set of standards. The well-fingered Soil Survey Field Handbook and Soil Colour Charts provide guidance on sampling. Nicki provides information (sediment description and interpretation) to the archaeologists (sometimes before they arrive on site) using very specific language. See 4. below.  |
4. Below is an example of the kind of information an Environmental Archaeologist collates. Nicki printed off a few reports evaluating material from boreholes at Dog Head Weir (Newbury) to give me an idea of the language. It was significant to me that Nicki uses her hands and eyes to classify materials just as I do. She gave the impression that she too enjoys having dirty hands!
Sediment description:
Compression Gap; Bands of 10YR 2/2 very dark brown-2/1 black humic detritus, 10yr 4/3 brown medium sand, 10YR 4/2 dark greyish brown tufaceous sand with abundant mollusc shell. Mollusc shells include aquatic and terrestrial species.
Interpretation: Banded alluvial sediments, alternating slow and fast moving water events with a significant period of permanently flowing water.
Sediment description:
Compression Gap; Bands of 10YR 2/2 very dark brown-2/1 black humic detritus, 10yr 4/3 brown medium sand, 10YR 4/2 dark greyish brown tufaceous sand with abundant mollusc shell. Mollusc shells include aquatic and terrestrial species.
Interpretation: Banded alluvial sediments, alternating slow and fast moving water events with a significant period of permanently flowing water.
KNUTSFORD RESIDUE: my own samples.
Pigment + medium = Paint.
Samples using PVA medium as a binder, varying quantites of water, and 2 paper surface qualities.
I will try different binders (oil, egg yoke, gum arabic, rabbit skin size).
Samples using PVA medium as a binder, varying quantites of water, and 2 paper surface qualities.
I will try different binders (oil, egg yoke, gum arabic, rabbit skin size).
Knutsford sample + PVA - no water added. Smooth paper. Lines scratched through back to paper surface.
Knutsford sample- extended with water and PVA (consistency of skimmed milk) applied onto dampened paper (Smooth/Hot Pressed).
Knutsford sample- extended with PVA (consistency of full cream milk) applied onto paper (Rough) and then sprayed with water. The particles granulate and settle in this way due to the curling of watercolour paper when damp and the texture of the paper surface.
Knutsford sample- A tonal gradation. Application of the sample with PVA (initially without water) then extending it with water (sprayed) and spreading with gravity. Paper (Rough).
I'd like to thank Nicki, Sarah and Holly Rodgers (Geoarchaeological Technician) who were extremely generous with information, soil and time. Graham Scott (Senior Archaeologist and Dive Superintendent) and David Norcott (Technical Manager, Geoarchaeology and Environmental) set up the meeting and for that I'm really grateful.
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