Improvements in bones and stones consolidating processes by vacuum system method

Abstract

The degradation of materials commonly starts on the surface of the object and proceeds towards inside through pores, increasing fractures and lesions. To restore mechanical and aesthetic characteristics, it is necessary by the application of consolidants to fill these weak points so that they become inaccessible to corrosive agents. Greater is the amount of consolidant that penetrates, greater the efficiency of the restoration. This is the limiting factor of many approaches which due to very tight pores result not fully successful. The consolidation under vacuum can help to pass these difficulties. So we have adopted it to restore Macco samples and tested to consolidate archaeological bones. The samples were consolidated by complete immersion under vacuum (−700 mm Hg), in a consolidant solution containing 8% w/V of diammonium phosphate. The success of the application to both the kind of samples is shown by microscope images, SEM-EDAX analysis, and weight variation.

Graphical Abstract

Keywords:

• Consolidation
• under vacuum
• archaeological bones
• Macco
• diammonium phosphate

Acknowledgements

We thank the Electronic Microscopy and Microanalysis Laboratory, Department of Earth Science, University of Rome “La Sapienza”, for having furnished SEM images. Special thanks to Prof. Alfredo Coppa, Department of Environmental Biology, University of Rome “La Sapienza”, for having furnished archaeological human bones and relative archaeological data.

Disclosure statement

We have no conflict of interest to declare.