@misc{10481/79828,
year = {2022},
month = {9},
url = {https://hdl.handle.net/10481/79828},
abstract = {Despite its fame as a chemically inert noble metal, gold (alloys) may suffer degradation under specific scenarios.
Here, we show evidence of electrochemically corroded gilded tin plasterwork in the Alhambra (Granada, Spain)
driving spontaneously made gold nanospheres with the optimal size (ca. 70 nm) to impart purple color at the surface.
Purple gold on damaged artworks is found sparsely, and its formation is not fully explained yet. We prove
that our decayed gold/silver-tin ornament is due to sequential/coexisting galvanic corrosion, differential aeration
corrosion, and dealloying of nonperfectly bonded and defect-based metals. Damage is enhanced by exposure to
a chloride-rich atmosphere. A white gypsum coat applied during the 19th century to overlap the unaesthetic
gilding assists observation of the gold-based purple color. Our work demonstrates gold dissolution, millimetric
migration, physical translocation, and deposition as secondary pure gold nanospheres over a centurial time scale
under natural environmental conditions.},
organization = {Junta de Andalucia	RNM-179	
P18-FR-4173},
organization = {Research Excellence Unit Science in the Alhambra from the University of Granada (Spain)	UCE-PP2018-01},
publisher = {American Association for the Advancement of Science},
title = {Natural corrosion-induced gold nanoparticles yield purple color of Alhambra palaces decoration},
doi = {10.1126/sciadv.abn2541},
author = {Cardell Fernández, Carolina and Guerra Tschuschke, Isabel},
}