Evaluation of laser cleaning of ancient Greek, Roman and Byzantine coins

Drakaki, E; Klingenberg, B; Serafetinides, AA; Kontou, E; Katsikosta, N; Tselekas, P; Evgenidou, D; Boukos, N; Zanini, A

dc.contributor.author	Drakaki, E	en
dc.contributor.author	Klingenberg, B	en
dc.contributor.author	Serafetinides, AA	en
dc.contributor.author	Kontou, E	en
dc.contributor.author	Katsikosta, N	en
dc.contributor.author	Tselekas, P	en
dc.contributor.author	Evgenidou, D	en
dc.contributor.author	Boukos, N	en
dc.contributor.author	Zanini, A	en
dc.date.accessioned	2014-03-01T02:46:47Z
dc.date.available	2014-03-01T02:46:47Z
dc.date.issued	2010	en
dc.identifier.issn	0142-2421	en
dc.identifier.uri	https://dspace.lib.ntua.gr/xmlui/handle/123456789/32852
dc.subject	Conservation	en
dc.subject	Copper alloy coins	en
dc.subject	Laser cleaning	en
dc.subject	Nd: YAG laser	en
dc.subject	SEM-EDX	en
dc.subject	Silver alloy coins	en
dc.subject.classification	Chemistry, Physical	en
dc.subject.other	Ancient Greeks	en
dc.subject.other	Athens , Greece	en
dc.subject.other	Corrosion products	en
dc.subject.other	Delivery systems	en
dc.subject.other	Laser cleaning	en
dc.subject.other	Long pulse	en
dc.subject.other	ND : YAG lasers	en
dc.subject.other	Optical fibre	en
dc.subject.other	Optical focusing	en
dc.subject.other	Oxidation layers	en
dc.subject.other	Q-switched	en
dc.subject.other	SEM-EDX	en
dc.subject.other	Side effect	en
dc.subject.other	Surface corrosion	en
dc.subject.other	Wet surfaces	en
dc.subject.other	Alloys	en
dc.subject.other	Chemical modification	en
dc.subject.other	Copper	en
dc.subject.other	Copper alloys	en
dc.subject.other	Copper deposits	en
dc.subject.other	Corrosion	en
dc.subject.other	Deposits	en
dc.subject.other	Neodymium	en
dc.subject.other	Optical fibers	en
dc.subject.other	Pulsed laser applications	en
dc.subject.other	Silver	en
dc.subject.other	Silver alloys	en
dc.subject.other	Silver deposits	en
dc.subject.other	Special effects	en
dc.subject.other	Surface cleaning	en
dc.subject.other	Neodymium lasers	en
dc.title	Evaluation of laser cleaning of ancient Greek, Roman and Byzantine coins	en
heal.type	conferenceItem	en
heal.identifier.primary	10.1002/sia.3482	en
heal.identifier.secondary	http://dx.doi.org/10.1002/sia.3482	en
heal.language	English	en
heal.publicationDate	2010	en
heal.abstract	Laser cleaning tests were performed on ancient coins, which belong to the collection of the Numismatic Museum of Athens, Greece. Silver and copper alloy coins with various types of surface corrosion and ground deposits were studied, using Q-switched (QS), long pulse (LP) and free-running (FR) Nd:YAG lasers and a range of laser-pulsing parameters on wet surfaces. A comparison among the different laser types was made, cleaning with an optical fibre delivery system and an optical focusing subassembly, or with the help of x-y microadjustable stage. It was discovered that the results of laser cleaning was influenced by the type of corrosion and the corrosion products or the ground deposits on the surface of the coins. The results, evaluated by objective and SEM-EDX observations, indicated that on silver alloy coins, different wavelengths could achieve a successful laser cleaning for several types of corrosion. On the other hand, laser cleaning could result in loss of the original surface in various cases of copper alloy coins, followed by frequent appearance of the oxidation layer underneath and partial removal of corrosion products and ground deposits. The optimum laser cleaning procedure was associated with the different types of coin corrosions. Special emphasis was stressed on the side effects of the procedures and, in particular, on the minimization of any chemical modifications and thermal results induced to the original surface of the coins. Copyright (C) 2010 John Wiley & Sons, Ltd.	en
heal.publisher	JOHN WILEY & SONS LTD	en
heal.journalName	Surface and Interface Analysis	en
dc.identifier.doi	10.1002/sia.3482	en
dc.identifier.isi	ISI:000281149700048	en
dc.identifier.volume	42	en
dc.identifier.issue	6-7	en
dc.identifier.spage	671	en
dc.identifier.epage	674	en