The northern rim of the granite massif consisting of biotite granite to granodiorite could be perhaps interpreted as a manifestation of some marks of zoned structure; this arrangement is reverse in comparison with ring complexes in Saudi Arabia where Harris (1985) reported a biotite granodiorite core and arfvedsonite granite rim.
Abbreviations: Fe-EC = ferro-eckermannite Fe-ED = ferro-edenite KAT = katophorite, ARF = arfvedsonite, RIEB = riebeckite, Mg-HB = magnesian hornblende.
By way of wrapping up, here is a short list of mineral occurrences which seem prolific right now and which, though not represented by single, large lots with single dealers at Munich, still imparted the impression of being "hot." The eudidymite, epididymite, arfvedsonite
Arfvedsonite [Na.sub.3]([Fe.sup.2+], Mg)[.sub.4][Fe.sup.3+][Si.sub.8][O.sub.22](OH)[.sub.2]
Arfvedsonite is a typical mineral of the eudialyte-aegirine-microcline zone.
Needles and microscopic stout prisms of arfvedsonite
occur in phonolite (Lindgren and Ransome, 1906; Birmingham, 1987).
Associated minerals are: aegirine, microcline, lorenzenite, nepheline, lamprophyllite, murmanite and arfvedsonite.
Associated minerals are: aegirine, arfvedsonite, eudialyte, potassic feldspar, sodalite, albite, carbonate-fluorapatite, lueshite, natrolite, and tuperssuatsiaite.
[ ] Arfvedsonite, [Mathematical Expression Omitted], mon., forms a series with Magnesio-arfvedsonite, Amphibole group, Can.
2], mon., forms a series with Arfvedsonite, Amphibole group, Can.
Astrophyllite Calciohilairite Catapleiite Chabazite Chlorite grp.
It is the rare amphibole species arfvedsonite
, in glistening black crystals to 2 cm, sometimes prismatic (resembling the well-known aegirine from the same place) and sometimes blocky.