This blog entry allows a very visual insight into our conservation progress.
Following condition assessing and documenting the cetacean specimens, treatment plans were made (see previous blog ‘Treatment decisions, decisions, decisions‘). Hands-on conservation commenced with dry cleaning the specimens one by one, to remove over 100 years worth of accumulated dust. This was followed by the second treatment phase focusing on addressing degraded oil residues formed on the surface of the bones.
Along the way, a few discoveries were made…
1) Removing layers of dust with a vacuum and brush
2) Reducing degraded oil residues on bone surfaces with an ammonia solution
3 Reducing degraded oil residues on cartilage/bone areas
4 Removing miscellaneous foreign matter
5 Discoveries made during treatment
Early (honest) treatment evaluation
While we are finding that oils on the bone surface are efficiently being solubilised by treatment with ammonia, we do not know how far the solution penetrates the bone and how much it facilitates a migration of oil from the core to the surface. It is difficult to judge to what extent treatment removes the currently degraded oil residues on the surface, without actively drawing out oil from the bone matrix. In some treated areas the bone surface takes on an orange tint, suggesting un-oxidised oils have indeed been drawn to the surface. Unfortunately at this stage, and without further analysis, it is difficult to predict the level of remaining oil in the bone and how distant in the future the cetacean specimens may require re-treatment.
While this phase of the cetaceans’ treatment is physically demanding (exasperated by working in Tyvek suits during a heatwave), and repetitive given that the project involves five large, suspended cetacean skeletons, the work is nevertheless rewarding. We’ve each adopted our own whale family members, who are affectionately seen through a new chapter in their museum lives.
Join us again for our next blog entry, where we will share images from our ‘bone rearticulation workshop’…
Gemma Aboe, Assistant Conservator