[roo-bid-ee-uh m-stron-shee-uh m, -shuh m, -tee-uh m]
a radiometric dating method whereby the ratio of rubidium isotope to strontium in a mineral is used to calculate the age of the mineral, based on the rate of radioactive decay of rubidium to strontium.
Origin of rubidium-strontium dating
First recorded in 1965–70
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
a technique for determining the age of minerals based on the occurrence in natural rubidium of a fixed amount of the radioisotope 87 Rb which decays to the stable strontium isotope 87 Sr with a half-life of 4.7 × 10 11 years. Measurement of the ratio of these isotopes thus gives the age of a mineral, for ages of up to about 4 × 10 9 years
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012