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Re: Pallasites and Tatahouine

At 10:32 AM 17/09/97 -0400, you wrote:
>I've been unable to solve the mystery of the three types of Pallasites -
>1)Eagle Station Trio Group, 2)Pyroxene Group, 3)Main Group.  Can anyone give
>examples of each and what the differences are?

In 1977 Edward Scott proposed a division of various pallasites into groups
based on their differeing compostions of Ni, Ga, Ge, Au:

Eagle Station Group- Ni 7.8-11.7% etc: Cold Bay Eagle Station, Itzawisis.

Main Group- Ni 14-16% etc: Admire, Ahumada, Albin, Brahin, Brenham, Dora,
Esquel, Finmarkin, Giroux, Hukittta, Imilac, Krasnoyarsk, Marjalahti, Mount
Vernon, Newport, Santa Rosalia, South Bend, Thiel Mountains

Anomalous Group- Metal compositions appropriate to high Ni Main Group
members but fayalite contents are too high for Main Group: Rawlinna,
Springwater, Phillips County.

In 1995, J. Boesenberg et al. proposed a Pyroxene Pallasites- a new
Pallasite Grouplet- based on Cr, Co, Ni, Cu, Ga etc: Vermillion,
Yamato-8451. Note however, there is no visual similarity between these two.

Joel Schiff