A first time for everything!

In the practical part of our course, we all received a metal coin, waterlogged wooden treenail and waterlogged leather to treat. This gives us valuable experience in how to treat these kinds of objects and encourages us to link theory with practical treatments.

Metal Coin

So we received our very first objects; a silver 1696 Sixpence for Sam and a Shilling for Tanya.

Both were tarnished and had adhesive and fibres stuck to one side.

At first, we spent the majority of the time just staring at them, wondering what on earth we were supposed to do and how everyone else seemed to know what they were doing. Eventually with some help from the tutors, we pulled ourselves together and started thinking logically.

The conservation requirement was to clean for display – remove the adhesive and fibres, and remove some of the tarnishing if necessary.

We had to figure out exactly what the problems were (adhesive, fibres, tarnishing) and how to solve them. There are a lot of solvents in the lab that can remove adhesives but we used acetone because research told us that it seemed to be the least harsh and most effective for the job.

Did you know? Nail varnish remover is made from Acetone and can be used to remove stubborn adhesives and tape!

Acetone and a cotton swab removed the fibres along with the adhesive - this was surprisingly effective and the removal was much quicker than either of us had expected. Two problems solved!

We also used a cotton swab with calcium carbonate in water to remove some (but not all!) of the tarnish to keep some of its evidence of use. This turned out to be more difficult – it is hard to get an even ‘old’ look without making super shiny spots. It was almost like using sandpaper to remove a very thin coating of tarnish.

And so here it is – one of our very first conserved objects!

Before

 After

Waterlogged Wooden Treenail

We then received waterlogged wooden treenails, recovered from Newport Ship. The conservation requirement here was different; these treenails are going to be handled by visitors to the museum. This meant that after treatment, it should still look and feel like wood (but dry!)

Waterlogged: When most of the spaces in an object have been filled with water, which is now supporting it. Waterlogged objects can come from underwater or burial.

Wet wood!

The first step in successfully drying waterlogged objects is to keep them wet! Removal of the water without replacing it will result in collapse. To prevent this collapse, we bulked (filled the spaces that needed support) our treenails with Polyethylene Glycol (PEG) before freeze-drying.

Fun fact: If you check your shampoos and/or body wash, you might find that there is PEG in there too!

Freeze-drying involved freezing the treenail before placing into a vacuum; the ice inside the wood then changed straight into vapour, missing out the liquid phase and leaving the PEG in its place as structural support.

When they came out of the freeze-drier, the treenails were nice and dry! 

Nice and dry!

Waterlogged Leather

Another waterlogged object we received were pieces of leather excavated from Bute Park outside Cardiff Castle. What look like scraps of leather are actually really awesome because it is a part of history from right outside of our lab!

Wet

You would think an acidic environment is bad, but leather is slightly acidic. This is why we checked the acidity of the water when we were storing them.

We then placed the leather in ethylenediaminetetraacetic acid—say that five times fast! It’s more commonly known as EDTA, a chelating agent that draws out potentially damaging metals from the leather.

We had to work out the percentage of glycerol in water we needed and used it in the leather in the same way that we used PEG for the waterlogged wood. We then shaped the leather into how we wanted it before freeze-drying.

Dry!

These were some of our group projects that we worked on alongside solo objects. So many objects, so little time! Stay tuned for more!