Hello Jeff, Greg, and List, Here is what I can contribute from the two references cited. Enjoy!
Cheers, Bernd Jeff wonders: Well that is one very cool looking feature indeed! And that's a good question Greg. But the thing that gets me is that the Widmanstätten pattern (1) is basically complete. And what is that grayish material? It looks a little like troilite or cohenite (2). And then there are the small bright silver blobs (3) inside that material. Schreibersite? (1) U.B. Marvin: Albion a IVA fine octahedrite, is unique in having vugs scattered throughout the otherwise orderly Widmanstätten structure... (2) U.B. Marvin: The spheroidal masses consist mainly of irregular kamacite grains 1-35 mm across, containing 2-3.5 wt% Ni...thin, branching films of troilite... (3) U.B. Marvin: ... a few rounded segregations of Ni-rich tetrataenite with 55.6 wt% Ni Greg would like to know: Do those look like 'melted' matrix droplets forming while this meteorite went through super heating at some point and created the gaseous voids (vugs)? M.E. Petaev: The crystalline linings in the vugs of the Albion iron, described in our companion paper, provide clear evidence of deposition from a fluid phase - most likely a vapor - that passed through the mass of iron at a late stage in its history. References: Marvin U.B. et al. (1996) Drusy vugs in the Albion iron meteorite: Mineralogy and textures (abs. Meteoritics 31-4, 1996, A083). Petaev M.E. et al. (1996) Drusy vugs in the Albion iron meteorite: Early speculations on the origin (abs. Meteoritics 31-4, 1996, A107). ______________________________________________ http://www.meteoritecentral.com Meteorite-list mailing list [email protected] http://six.pairlist.net/mailman/listinfo/meteorite-list
