40581
Accession Number
11420
Title Of Article Chaper
Beta emission radiography, a new philatelic tool
Title Of Journal Book
American Philatelist
Volume
97
Issue
7
Pages
620-622
Collation
Photos.
Publisher City
Altoona, PA
Language Of Text
English
Literature Type
Serial
Literature Level
Analytic
Abstract
Described is use of radiocarbon (<sub>14</sub>C) as a source of beta particles for making radiographs of postage stamps to show watermarks in the paper. This is useful, it is reported, for distinguish-ing marks made in manufacturing from marks impressed after manufacturing. Exposure times of 24 hours are suggested.
pub_id
40581