Subject: Time lapse films of deterioration
The Canadian Museum of Nature and the Canadian Conservation Institute, in a collaborative initiative, have produced time lapse sequences of mineral specimens deteriorating as a result of exposure to different risks. Two sequences are now available for viewing as video clips at the Canadian Museum of Nature web site at: <URL:http://www.nature.ca/english/movies.htm> One sequence depicts the arsenic sulfide mineral, realgar, crumbling on exposure to light, the result of a photo-induced phase transition. The second sequence depicts the highly soluble calcium-magnesium-chloride-hydrate mineral, tachyhydrite, dissolving at a relative humidity level above its deliquescence point. We believe that film sequences such as these can be powerful educational tools for those who believe that collections, especially geological collections, are quite stable and scarcely require special care for preservation. We would be interested in your reactions to these sequences and your thoughts about disseminating film sequences such as these as didactic tools. Robert Waller Chief, Conservation Canadian Museum of Nature Box 3443, Station D Ottawa, Ontario K1P 6P4 Canada 613-566-4797 Fax: 613-364-4022 *** Conservation DistList Instance 12:29 Distributed: Tuesday, September 22, 1998 Message Id: cdl-12-29-013 ***Received on Friday, 18 September, 1998