Table 1 Summary of Pb-Pb dates, petrology, μ values, and 238U/235U and Zn isotope compositions of individual chondrules.

Pb isotope data for the Allende and three chondrules from NWA 5697 (C1, C2, and C3) were previously reported by Connelly et al. (6) and are included here for completeness. P, porphyritic; NP, nonporphyritic; I, type I; II, type II. The 238U/235U uncertainties are propagated in the final age uncertainties. The Pb-Pb isochrons for three chondrules (5-C1, 5-C4, and 1-C2) project back to a modern terrestrial composition, and thus, accurate μ values cannot be calculated for these objects. The zinc isotope compositions are reported in δ notation, which reflects the per thousand (‰) deviations of the 66Zn/64Zn of the sample from the JMC Lyon standard.

ChondruleTexture and typePb-Pb age (Ma)μ238U/235Uδ66Zn (‰)
NWA 5697
  5-C1NP, II4567.61 ± 0.54137.807 ± 0.033
  2-C1NP, I4567.57 ± 0.5633137.779 ± 0.022−0.38 ± 0.05
  5-C2NP, II4567.54 ± 0.5221137.756 ± 0.029−1.07 ± 0.05
  5-C10NP, II4567.41 ± 0.5738137.786 ± 0.013−1.41 ± 0.05
  C1NP, I4566.67 ± 0.4323137.786 ± 0.013
  D-C3P, II4566.58 ± 0.5751137.786 ± 0.013−1.12 ± 0.05
  5-C4P, II4566.56 ± 0.53137.786 ± 0.013−1.15 ± 0.05
  3-C5P, II4566.20 ± 0.6328137.807 ± 0.026
  C3NP, II4566.02 ± 0.26183137.786 ± 0.013
  11-C1NP, II4565.84 ± 0.7232137.779 ± 0.030
  C2P, I4564.71 ± 0.3063137.786 ± 0.013
  11-C2NP, II4564.65 ± 0.46108137.755 ± 0.025−2.20 ± 0.05
  3-C2P, II4563.64 ± 0.5194137.786 ± 0.013−1.13 ± 0.05
NWA 6043
  1-C2P, I4567.26 ± 0.37137.786 ± 0.013
  2-C2P, II4565.06 ± 0.40104137.786 ± 0.013
  2-C4P, II4564.50 ± 0.7093137.786 ± 0.013
  0-C1P, II4563.24 ± 0.6258137.786 ± 0.013
NWA 7655
  1-C7P, II4566.51 ± 0.372137.786 ± 0.013
  1-C2P, I4564.54 ± 0.3451137.786 ± 0.013
  1-C6P, II4564.27 ± 0.499137.786 ± 0.013
Allende
  C30P, II4567.32 ± 0.4229137.786 ± 0.013
  C20P, II4566.24 ± 0.6326137.786 ± 0.013