Chemical and mineralogical analyses established it as a type II carbonaceous chondrite (C2). Murchison consists largely of fine-grained black matrix which has been identified as primarily a mixture of two iron-rich, low-aluminum chamosite polytypes. Contained in the matrix are four main types of inclusions: (1) single crystals and crystal fragments, (2) loosely aggregated clusters of crystals ("white inclusions"), (3) discrete true chondrules, (4) xenolithic fragments of two other meteorite types (mostly a unique kind of C3 chondrite). The first type of inclusions consists of unzoned and highly zoned olivines, unzoned (disordered and ordered) orthopyroxenes, clinoenstatite, and rare diopside. Prominent minor phases are calcite, chromite, metal (with occasional traces of schreibersite), troilite, pentlandite, and two phases that could not be fully characterized. The second type of inclusions consists primarily of grains of olivine (Fa 0 to Fa 40), lesser low-Ca pyroxenes, and minor spinel, calcite, whewellite, hibonite, perovskite, chromite, pentlandite, and rare Ca-pyroxene. The true chondrules consist of olivine, Ca-poor pyroxene, occasional metal, and, in rare instances, one of the poorly characterized phases. The chondrules are not texturally typical of the ordinary chondrites, but resemble more closely those chondrules seen in C3 and C4 chondrites. The fourth type of inclusion consists mainly of distinct xenolithic fragments of a light blue-gray chondrite type that resembles certain C3 chondrites (like Vigarano), though not in all aspects. These xenolithic fragments consist of disequilbrated olivines and pyroxenes, abundant pentlandite and troilite, and virtually no metal. In addition, a single xenolithic fragment was found of an unknown meteorite type. Ca-and Al-rich glasses (of varying compositions) are found as blebs, with or without gas bubbles, contained within olivine crystals. The average Ca/Al ratio of these glasses approximates that for all meteoritic matter. They may represent early (nonequilibrium) subcooled condensates from the solar nebula. This nonequilibrium stage was apparently followed by equilibrium condensation through intermediate to low temperatures at which the layer-lattice phases condensed in abundance and incorporated crystals and fragments of the higher temperature phases. OFFICIAL PUBLICATION DATE is handstamped in a limited number of initial copies and is recorded in the Institution's annual report, Smithsonian Year. SI PRESS NUMBER 4784. SERIES COVER DESIGN: Aerial view of Ulawun Volcano, New Britain. Library of Congress Cataloging in Publication Data Fuchs, Louis H. Mineralogy, mineral-chemistry, and composition of the Murchison (C2) meteorite. (Smithsonian contributions to the earth sciences, no. 10) I. Meteorites. I. Olsen, Edward John, 1927-joint author. II. Jensen, Kenneth J., joint author. III. Title. IV. Series: Smithsonian institution. Smithsonian contributions to the earth sciences, no. 10. QE1.

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Internal cation mobilities of Li + and K + in the system (Li-K)CI were determined experimentally using the counter current eleetromigration method over the temperature range 700-778 K, with initial equivalent fractions of KCI of 0.356, 0.416, and 0.451. The relative difference in internal cation mobilities ofLi + and K + was found to reach as much as 7% in this range.Lithium-aluminum/iron sulfide cells that contain multicomponent molten salt electrolytes such as (Li-K)C1 mixture are currently under development for energy-storage applications (1). During charge or discharge of such cells, composition gradients of ions, Li + and K + are induced within the molten salt by the electrode reactions. As a result, the salt compositions are shifted locally from the liquidus range, and precipitation of a solid phase may occur. In lithium/ sulfide cells, which are operated at a temperature range of 400°-430°C in (Li-K)C1 eutectic, Askew and Holland (2) noted that the lithium electrode was severely polarized when .discharged at high current densities. They conjectured that the polarization was caused by precipitation of LiC1 at the lithium electrode. Willars et al. (3) found that the cell capacity was inversely proportional to discharge rate, and the result was interpreted in terms of electrolyte phase separation at the iron sulfide electrode. Braunstein and Vallet (4) and Pollard and Newman (5) calculated current-induced composition profiles of LiC1 and KC1 in lithium/ sulfide cells containing (Li-K)C1 electrolyte. Furthermore, Vallet et al. (6) predicted a composition profile that indicates an increased KC1 concentration near the cathode. More recently, they presented direct evidence of KC1 precipitation (7). Furthermore, they have shown that the composition profile depends not only on the initial composition of the electrolyte, but also on the current density and distance between electrodes. The high KC1 concentration also favors the formation of J-phase (LiKsFe2~S26C1) in the iron sulfide electrode (8). Transition time required for the separation of the components, which was estimated by Braunstein and Vallet (5), is correlated with the transference number and diffusion coefficient. However, transference number is directly related to the emf because the concentration polarization is involved. Thus it is necessary to know the mobilities of the ions at the operating temperature for accurate determination of the transference numbers. At present, the experimental data reported on the mobilities of Li+ and K + in the system (Li-K)C1 are limited to the temperatures at 913 (9) and 1100 K (10), which are much higher than the normal operating temperature of lithium/iron sulfide cells, i.e., 723 K.In this study, the internal cation mobilities, ~.e., the cation mobilities relative to the common anion, were measured in the system (Li-K)CI at the cell operating temperature range by the counter current electromigration method developed by Klemm (11) and Okada (12).

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