THE VISCOSITY OF THE LUNAR MANTLE IS CRITICAL FOR UNDERSTANDING THE THERMAL AND CHEMICAL EVOLUTION OF THE MOON. HIGH-TI LUNAR BASALTS HAVE UP TO 16.5 WT% TIO2 SUGGESTING THEY ORIGINATE FROM AN ILMENITE-RICH MANTLE SOURCE. HOWEVER THE VISCOSITIES OF ILMENITE-BEARING MAFIC AND ULTRAMAFIC ROCKS RELEVANT TO THE LUNAR MANTLE HAVE NOT BEEN MEASURED IN THE LABORATORY. RECENT EXPERIMENTAL WORK SHOWS THAT ILMENITE (FETIO3) IS NEARLY FOUR ORDERS OF MAGNITUDE WEAKER THAN DRY OLIVINE AT MANTLE CONDITIONS. RHEOLOGICAL MIXING MODELS PREDICT THAT A LUNAR MANTLE WITH A SMALL AMOUNT OF ILMENITE COULD BE DRAMATICALLY WEAKER THAN AN ILMENITE-FREE MANTLE. TO CONSTRAIN THE VISCOSITY OF AN ILMENITE-BEARING LUNAR MANTLE NEW EXPERIMENTS ARE NEEDED TO EVALUATE THE EFFECT OF SMALL AMOUNTS OF ILMENITE ON TWO-PHASE AGGREGATE RHEOLOGY AND TO EVALUATE THE EFFICACY OF USING AGGREGATE RHEOLOGY MODELS TO PREDICT EFFECTIVE VISCOSITIES RELEVANT FOR THE MOON USING END-MEMBER FLOW LAWS. WE PROPOSE TO MEASURE THE EFFECTIVE VISCOSITY OF ILMENITE-OLIVINE AGGREGATES IN GRIGGS ROCK DEFORMATION EXPERIMENTS AT BROWN UNIVERSITY AND TEXTURALLY CHARACTERIZE THE EXPERIMENTS AT THE UNIVERSITY OF TEXAS AT AUSTIN. WE WILL ALSO INVESTIGATE THE EFFECTS OF FE/MG RATIO ON ILMENITE RHEOLOGY WHICH IS REQUIRED TO EVALUATE MECHANICAL DATA FROM THE TWO-PHASE EXPERIMENTS USING AGGREGATE RHEOLOGY MODELS. OUR LABORATORY APPROACH CAPITALIZES ON OUR EARLIER WORK AND TAKES ADVANTAGE OF THE TECHNICAL STRENGTHS OF THE TWO INSTITUTIONS. THE PROPOSED STUDY IS TIMELY IN LIGHT OF RECENT LUNAR MISSIONS AND GROUND BASED STUDIES THAT HAVE GENERATED A LARGE AMOUNT OF GEOPHYSICAL OBSERVATIONS AND THAT HAVE STIMULATED A NEW WAVE OF STUDIES OF THE INTERNAL STRUCTURE OF THE MOON AND THE LONG-TERM EVOLUTION OF THE LUNAR MANTLE AND LUNAR CORE.