21258 - New Unpublished Complete Iron IAB Meteorite 2553g Fallen in Algeria

A little over a month and a half ago, I published an IAB iron meteorite in this group, which I bought as possible NWA fallen in Algeria. However many of you questioned its origin due to its enormous similarities with Nantan. In this way I decided to start his study to get out of doubt.

I sent a sample to the Laboratory of Applied Petrology of the Department of Earth Sciences of the University of Alicante. Here I show you what analysis we did:

The polished surface of the sample was analyzed in the Scanning Electron Microscope. Thesample is mainly constituted by kamacite (Fig. 2 and 3) and in smaller quantity by taenite (Fig. 2). Taenite crystals are included in Kamacite. It presents areas of alteration where the kamacite has been transformed to
akaganeite (Fig. 2 and 4). These areas of alteration are visible by dark areas on the cut and polished surface. Although more analysis is needed, the sample is an Iron meteorite, and the appearance of kamacite and taenite, as well as the lines of Widmanstätten suggests that can be an octaedrite. It seems very similar to Nantan, but we still have to do the analysis of the trace elements in parts per million to compare it with Nantan and get out of doubt. Those analyzes will have to be done by a laboratory in Canada! But in the meantime we already have the first part!

Mineralogy and textural properties of samples were studied on (30m-thick) polished thin sections using transmitted and reflected light microscopy at LPA (UA) and UGR.