Author
Geyh, Mebus A.Issue Date
1990-01-01Keywords
counting gasHannover Laboratory
lithium
aliphatic hydrocarbons
acetylene
alkynes
decontamination
alkali metals
hydrocarbons
techniques
metals
organic compounds
organic materials
sample preparation
methods
C 14
carbon
isotopes
radioactive isotopes
carbon dioxide
absolute age
Metadata
Show full item recordCitation
Geyh, M. A. (1990). Radiocarbon dating problems using acetylene as counting gas. Radiocarbon, 32(3), 321-324.Journal
RadiocarbonDescription
From the International Workshop on Intercomparison of Radiocarbon Laboratories.Additional Links
http://radiocarbon.webhost.uits.arizona.edu/Abstract
An investigation of inconsistent Hannover results in the International Collaborative Study (ICS) led to the conclusion that the main reason was contamination of the acetylene used as counting gas with recent and/or fossil carbon by the lithium used for its preparation. Despite the high level of purity of the lithium guaranteed by the producer and storage under argon in cans, different charges were partly covered with contemporary lithium carbonate and fossil oil sometimes was used to preserve the metal. Thorough cleaning of the surface of the lithium rods decreased the contamination but did not remove it entirely, which is evidenced in the wider scatter of the counting rates of various background gases than that of radiocarbon-free tank acetylene. As a result of the high risk of contamination with fossil and/or recent carbon from the acetylene counting gas, the high price of lithium, and the time-consuming preparation, the Hannover 14C Laboratory will use carbon dioxide instead of acetylene as counting gas in the future.Type
Proceedingstext
Language
enISSN
0033-8222ae974a485f413a2113503eed53cd6c53
10.1017/S0033822200012947