title: Lead Isotope Variation with Growth Zoning in a Galena Crystal.
abstract: A large crystal of lead sulfide from Picher, Oklahoma, has significant differences in isotopic composition of lead in successive growth zones. Lead isotope ratios in the parent ore-fluid evidently changed with time during crystal growth. The growth history of this crystal, interpreted quantitatively, points to a tentative hypothesis of genesis of Mississippi Valley deposits of lead and zinc.
authors.forename: R S
authors.initials: RS
authors.lastname: Cannon
authors.forename: A P
authors.initials: AP
authors.lastname: Pierce
authors.forename: M H
authors.initials: MH
authors.lastname: Delevaux