Pt-bearing phases in ocean Mn-Fe crusts on basalts

Pt-bearing phases in ocean Mn-Fe crusts on basalts

N.S. Rudashevsky, Yu.L. Kretser, L.I. Anikeeva, S.I. Andreev

Pacific ocean, 19°38’ N.l., 175°48’ W.l.

Weight of sample - 300 g

(wt.%): Mn 24.2 Fe 12.6 Ni 0.59 Co 0.72 Cu 0.13

(ppm): Pt 0.35 Pd 0.0052 Au 0.005 Ce 1180 La 190

Heavy mineral phases:

1) oxides — wustite+magnetite, ilmenite, titanium magnetite, chromite, zircon, unnamed ZrAl2O5;

2) sulphides — pyrite, chalcopyrite, sphalerite, chalcosine, bornite, heazlewoodite, molybdenite, tennantite and galena;

3) native metals — native iron, nickel, taenite, copper, brass, bronz and lead;

4) other minerals — goethite, apatite, barite, bastnasite-(Ce)

Mineral parageneses:

1) matrix-minerals — Mn-Fe hydroxides, goethite, apatite, barite;

2) minerals from basalts — ilmenite, titanium magnetite;

3) cosmic minerals — microspheres of wustite+ magnetite+ taenite;

4) voletile fluid minerals — all native metals, sulphides etc.


Pt-bearing phases of ocean Mn-Fe crusts on basalts; heavy concentrate, SEM images (BIE).

HOX — (Fe,Mn) — Fe-Mn hydroxides; BRS — native brass (Cu,Zn,Sn); BRNZ — native bronz (Cu,Sn,Zn,Ag), AP — apatite, RSB — rustenburgite, Fe3Si, Fe2Si, Fe5Si3, (Cu,Pt)5Si and (Cu,Pt)4Si — unknown phases.