Orickite and coyoteite, two new sulfide minerals from Coyote Peak, Humboldt County, California

摘要: Orickite and coyoteite occur with rare alkali iron sulfides in a mafic alkalic diatreme near Orick, Humboldt County, California. Both minerals are very rare, only few milligrams of each have been found. Orickite, Na,KrCuse5Fer.ooSz.zHzO (x,y < 0.03, z 0.5), is hexagonal; a:3.695, c : 6.164 (both t0.0lA); D = 4.212 g cm-3 forZ:4. The six strongest lines the X-ray diffraction powder pattern [d A, t, (*ttt):3.08, 100, (002); 3.20 90, (100); 2.84,60, (l0l); 1.73,55, (103); 1.583,30, (ll2);2.20, 15, (102). mineral brass yellow opaque, weakly pleochroic, but strongly anisotropic (from grayish brown to blue) reflected light. compositionally iron-rich chalcopyrite, may be related synthetic chalcogenides having distorted wurtzite-\2[I) structure. Coyoteite, NaFe3S5.2H2O, triclinic, Pl or Pl; 7.409(8), b 9.881(6),