Rock of ages--cleft by laser

Lewin, Roger
September 1991
New Scientist;9/28/91, Vol. 131 Issue 1788, p36
Looks at the use of lasers for determining a precise age for rocks. The advantages of using lasers; The conventional potassium/argon technique for dating; Single crystal dating and problems this method overcomes. INSET: Hatian tektites date the demise of the dinosaurs.


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