bituman

The bitumen sealing the lid has also started to crack – not surprising, given that it’s ninety-nine years old! We’ll carefully remove the lid and clean off all the bitumen, then we’ll re-seal the jar with silicone. We don’t use bitumen to seal our fluid specimens – it gives off harmful fumes when heated, and is no longer considered safe to use. We’ll also replace the porous cork bung with a silicone one, to keep any future evaporation to a minimum. With any object that we need to work on, our aim is to intervene as little as possible, while still ensuring that the specimen will remain in good condition over a long period of time. In particular, we try not to take delicate specimens such as these out of their glass jar, as removing them from the supporting fluid can cause damage. We also need to consider whether any of our changes will have an impact on Lo Bianco’s original preparation.