EARTHTIME reference zircon
Anorthosite from the Duluth Complex, Minnesota

Sample FC-1 Zircon was extracted from a sample of gabbroic anorthosite of the Duluth gabbro complex (ca 1099.0 Ma) at Forest Center, MN and was originally called FC-1 (not to be confused with the Fish Canton Tuff sample of the same name). It has been used as a U-Pb standard for SIMS analyses at the RSES of the ANU and many other laboratories are experimenting with it as a standard.

EARTHTIME obtained a large amount of sample from the Geology Club at the University of Minnesota at Duluth. The processed sample yielded a large amount of zircon and baddeleyite. If you would like an aliquot of these grains for analysis by ID-TIMS as part of the EARTHTIME initiative, please contact S.A. Bowring.

If you desire unprocessed sample, please contact John Goodge of the University of Minnesota at Duluth: Department of Geological Sciences, University of Minnesota, 1114 Kirby Dr., Duluth, MN  55812 USA, Tel. 218-726-8486



Sample descriptions for EARTHTIME reference zircon and baddeleyite anorthosite from the Duluth complex, Minnesota, USA

Duluth complex: anorthosite (sample FC-1)
Three representative zircon grains were treated using CA-TIMS and have 0.8 to 2.0 ng of radiogenic Pb. Thus precise and accurate results can be obtained with these grains with total procedural blanks less than 10 picograms.
Duluth complex: anorthosite (sample FC-1)
Three representative baddeleyite grains have 0.5 to 0.8 ng of radiogenic Pb. Thus precise and accurate results can be obtained with these grains with total procedural blanks less than 10 picograms.



EARTHTIME is supported by the National Science Foundation.