title: Terrestrial Ratio of Potassium to Rubidium and the Composition of Earth's Mantle.
abstract: The ratios of potassium to rubidium determined for a series of oceanic volcanic rocks suggest that the K/Rb ratio of the upper mantle exceeds 1500. The similarity between this inferred K/Rb ratio for the mantle and that found in some achondritic meteorites suggests a similar overall composition for these materials.
authors.forename: P W
authors.initials: PW
authors.lastname: Gast