Hallo,
hab versucht eine Klassifiaktion für das silikatreiche NWA eisen zu finden. (Posting von der US Liste)
weiss wer, bei wem die offizielle Klassi durchgeführt wird?
Attempt for a preliminary classification of the new NWA silicated iron. I have made several polished sections, and found following:
It shows octahedral structure with different rounded and angular silicate inclusions.
Most of the silicate inclusions are equigranular in texture, with typical 120 degree triple junctions. (Very similar to the Winonaites). In this inclusions sulfate is present.
There are rarer silicate inclusions with less sulfate, but abundant metal. These inclusions look chondritic and are equilibrated (both metal and silicate).
In places are euhederal olivines as well as some chromian – diopsides with dark green color.
Based on these observations (without chemical analysis) it should belong to the IAB Iron complex (despite the fact of the “anomalous” iron rich silicate inclusions.)
Let’s see what the official classification will be….
dellenit