WADSLEYITE, NATURAL F-(Mg, Fe).Sion from the PEACE
Canadian Mineralogist Vol. 21, pp. 29-35(1983) WADSLEYITE,NATURAL F-(Mg, Fe).SiOnFROM THE PEACERIVEH METEORITE G. D. PRICE, A. PUTNIS eNp S. O. AGRELL Departmentof Earth Sciettces,University ol Cambridge,Cambridge CB2 3EQ, England D. G. W. SMITH Departmentof Geology,University of Alberta, Edmonton,Alberta T6G 2E3 ABsrRAcr tion 6lectroniquesont compatiblesavec le groupe spatialImma. La nouvelleespdce honore feu le Dr. Wadsleyite, a new mineral species, occurs as a A.D. WadsleST'. fine-grained material in fragments within a vein (Iraduit par la R6daction) in the Peace River meteorite (Alberta); it was formed by a series of polymorphic phase trans- Mots clds: wadsleyite,nouvelle espdce,F-(MeFe)z formations, from olivine and ringwoodite, during SiOr,polymorphe, min6ral du manteau,m6t6orite, (Alberta). an extraterrestrial shock event. Wadslevite has the 6v6nementde choc, PeaceRiver structure of the P-phase polymorph of (IvIg,Fe)cSiOr and an ideal composition of (Mg,."Feo.JSiOo.Single INtnoouctIox crystals of wadsleyite rarely exceed 5 p,m in dia- meter; polycrystalline aggregates are transparent Wadsleyite, a new mineral species found in with a pale fawn coloration and a bulk index of the Peace River meteorite (Alberta), is the refraction of 1.76. The strongest six reflections in naturally occurring B-phase polymorph of (Mg, the X-ray powder-diffracrion pattern td in A qy Fe)rSiO.. The occurrence of the p-phase as an (/r A l)l are: 2.89(m) (040), 2.69(m) (013), 2.45(s) intermediate in the high-pressuretransformation (lal), 2.04(s) (240), r.57(m) (303), L4aG) Qa{. of magnesium-rich olivine to its spinel-structure Wadsleyite is orthorhombic with a 5.70(2), b ll.Sl polymorph was first reported Ringwood (7), c 8.24(4) L, V Slt(l) ]r", Z- 8 and.
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