Curator's Choice: Polychrome Coiled Basketry Bowl
Conservation Report

Polychrome Coiled Basketry Bowl Main Page

Dr. Nancy Odegaard
Conservator and Head of Preservation

Description and Technical Analysis:

This basket is bowl or basin shaped. The interior is the workface and the weaving is to the right The base is flat and the sides are flaring. The start of this basket is damaged but there appears to be frayed grass fiber. The fag ends are both bound under and clipped short on the workface. The moving ends are more often bound under on the non-workface. The finish is a herringbone or braid finish with blunt end. Stitches are 2mm and 5 stiches per cm; there are 2.5 coil rows per cm.

Treatment:

We decided to clean the basket partially, in order to better reveal the extreme difference. The surfaces were darkened and fully obscured the design. The very soiled surfaces are probably a result of both indigenous use and collector display / storage conditions. The extensive wear on the exterior base and stitch loss to the rim is more likely from cultural use. The damage to the start and the vertical break from the rim are both most likely a result of poor mounting and handling. Hanging a basket from the center with no support causes deformation including a flattening on one side and over curvature on the other.

Image 1 - Cleaning with CO2 snow to remove loose particulates from surfaces

Once examined, one side of the basket was vacuumed using a soft fan-shaped brush and a dental vacuum set to low suction. Next, that same side of the basket was cleaned using a specialized nozzle and the “snow” from compressed carbon dioxide gas. (Image 1) This technique is new to the field and under development here at ASM and we are still working out the protocols and procedures that best suit basketry. This basket has been a challenge for the technique but has helped identify modifications to the technique.

Finally, in several areas a small amount of ethyl alcohol was used with swabs to remove some remaining residue. (Images 2 & 3) This worked most effectively on the juncus stitches. We plan to analyze the residue using chemical and instrumental techniques.

Image 2 - Treatment with a small amount of ethyl alcohol on swabs to remove some remaining residue.

Image 3 - Close-up view after treatment with a small amount of ethyl alcohol. This helped identify the red material as juncus stem.

Image 4 - The break spanning nine coil rows.

The break that included nine coil rows (Image 4) was aligned and stabilized with adhesive at strategic points where the bundle materials met. When the remainder of the basket is cleaned it will probably be necessary to add additional stabilizing material to this break for greater security. I will likely use a strip of Tyvek fabric that has been toned to match the basketry fiber and secure it through the areas that are already lost. I want the repair to blend in but I don’t want to use plant materials as I don’t want to confuse my conservation treatment with the original weaving.

Photos by Gina Watkinson

Polychrome Coiled Basketry Bowl Main Page