[meteorite-list] Whole individual

From: joseph_town_at_att.net <joseph_town_at_meteoritecentral.com>
Date: Thu Mar 9 22:26:46 2006
Message-ID: <031020060326.4303.4410F1F300014922000010CF21602806510299019BA1089F0A9C0106_at_att.net>

List,

Back to the whole individual question. Really fresh specimens can be confusing at a glance. Many appear to be fragments with fresh exposed matrix, exposed as if they broke on impact with a hard surface. After a second look I see the light matrix from the exposed face frosted over the fusion crust without any sign of secondary ablation color change. Flakes of heavy crust missing with splotches remaining, like missing shuttle tiles, the exposed matrix still pristine showing no secondary burn. Spatters of metal splashed on the outside of the black crust like someone splashed solder on it.

It appears that heat was no longer the primary factor involved, so what ensued in those final seconds or a fraction, that determined these effects? Are these common characteristics of a fresh chondrite fall? If not, maybe the velocity was greater than prescribed. Could the last blast of a fragmenting, soon to be meteorite, cause the fragments to gain velocity, lose heat and undergo changes caused by pressure alone?

It's difficult enough for me to comprehend fresh stuff. It's crazy to think about finds and how to decide if they are whole individuals.

Bill
Received on Thu 09 Mar 2006 10:26:43 PM PST