The term 'wax bloom' is used to describe a thin whitish crystalline layer that develops on the surface of beeswax objects under specific conditions. This phenomenon is undesirable, especially in the cases of objects with aesthetic or informational value, such as wax sculptures or historical seals. A combination of solid-state NMR and FTIR measurements allowed to obtain fairly detailed insight into the problem and to suggest a probable mechanism of its development. Secondary crystallization of unsaturated hydrocarbons from beeswax was determined as a primary cause. After the macroscopic solidification of beeswax from the melt, these molecules remain for months in a highly mobile, liquid-like state. This facilitates their diffusion to the surface, where they eventually crystallize, forming the 'wax bloom' effect. Although these results are of particular interest with respect to the conservation of beeswax artifacts, they are relevant to this material in general and help with understanding its unique properties.
Keywords: 13C; NMR; beeswax; crystallization; efflorescence; unsaturated hydrocarbons; wax bloom.
Copyright © 2015 John Wiley & Sons, Ltd.
Non-destructive imaging of fragments of historical beeswax seals using high-contrast X-ray micro-radiography and micro-tomography with large area photon-counting detector array.Micron. 2016 Dec;91:22-28. doi: 10.1016/j.micron.2016.09.006. Epub 2016 Sep 16. Micron. 2016. PMID: 27684352
Calibration of Raman spectroscopy at 1064 nm for beeswax quantification.Appl Spectrosc. 2007 Nov;61(11):1259-64. doi: 10.1366/000370207782597157. Appl Spectrosc. 2007. PMID: 18028707
A comparative study on the artificial UV and natural ageing of beeswax and Chinese wax and influence of wax finishing on the ageing of Chinese Ash (Fraxinus mandshurica) wood surfaces.J Photochem Photobiol B. 2019 Dec;201:111607. doi: 10.1016/j.jphotobiol.2019.111607. Epub 2019 Aug 27. J Photochem Photobiol B. 2019. PMID: 31710927
Mobile NMR: An essential tool for protecting our cultural heritage.Magn Reson Chem. 2017 Jan;55(1):33-37. doi: 10.1002/mrc.4544. Magn Reson Chem. 2017. PMID: 27748982 Review.
Beeswax: A minireview of its antimicrobial activity and its application in medicine.Asian Pac J Trop Med. 2016 Sep;9(9):839-843. doi: 10.1016/j.apjtm.2016.07.003. Epub 2016 Jul 26. Asian Pac J Trop Med. 2016. PMID: 27633295 Review.