Olive Jones (Parks Canada Glass Glossary 1989:12) suggests using UV light
to determine the presence of lead in glass.  English lead glass will
fouresce ice-blue and demi-lead glass is ice-purple under ultra-violet
light.  But as to why is does this, Jones only says it is a "complex
phenomena".


Ben Mortimer
National Parks and Native Sites Archaeologist
Parks Canada, OSC-Cornwall




                      Denis Gojak
                      <denis@BANKSIAHER        To:       [log in to unmask]
                      ITAGE.COM>               cc:
                      Sent by:                 Subject:  Glass that flouresces
                      HISTORICAL
                      ARCHAEOLOGY
                      <[log in to unmask]
                      >


                      04/04/05 03:17 PM
                      Please respond to
                      HISTORICAL
                      ARCHAEOLOGY






Hi all

A bit of a trivia question.

Attached is a link to Nature News, the chatty gee-whizz stories from the
august journal Nature.  This one is about a materials scientist who is
creating a reference collection of unusual materials [many weird
synthetics].  It contains the following paragraphs:

'Miodownik trawls the globe in search of additions to his collection. On a
recent trip to Australia, he found himself in the remote uranium-mining
town of Broken Hill in New South Wales. He started hunting through antique
shops there to find a special type of glass.

'Miodownik explains that in the early twentieth century people thought that
radioactive materials had beneficial health properties. For this reason,
they manufactured glassware containing uranium, especially in places such
as Broken Hill that had an abundance of the element.

'In the Australian antique shops, Miodownik flashed an ultraviolet light on
various glass pieces to find one that glowed, a sign that it contained
uranium. When he found a bowl that did just that, he brought it back to
London and added it to the library.

[full link - http://www.nature.com/news/2005/050328/full/050328-5.html]

Apart from the small matter of Broken Hill mining silver, lead and zinc and
no appreciable uranium, nor being a notable decorative glass manufacturing
centre, I was wondering from some of the many glass gurus on the list what
added elements cause flourescence such as described.  Was Dr Miodownik's
bargain hunting futile?

cheers

 Denis