in dichromic acid and circulating distilled water the crystals were then washed in dilute hcl re rinsed in circulating distilled water and air dried in a dust free laminar flow hood prior to cleaning a small hole was drilled 0 020 inch through the plane surfaces of each crystal near the rim to enable suspension by a thin pt wire optically transparent fully dense 8 65 35 plzt was prepared by gravimetric liquid phase sintering and by 34 hot pressing 34 as obtained commercially from honeywell inc the sintered samples were formed as discs 0 350 inch diameter and optically polished the commercial 34 hot pressed 34 samples were formed as discs 0 750 u00d7 0 030 inch and optically polished the discs were drilled and cleaned in the same manner used to drill and clean the linbo 3 discs thermogravimetric apparatus is used in conjunction with the slotted camp crucibles the single phase crystalline members were suspended from a cahn r 100 recording electrobalance by means of a pt wire such that they could be centered within the slotted crucible cavity an outer platinum muffel crucible was utilized to prolong the life of the plzt crucibles proper alignment of the single crystal linbo 3 samples within crucible cavities was complicated by a strong surface charge that caused their attraction to the cavity walls this surface charge was neutralized at room temperature by pre treating the sample and the crucible in gc spectrophotometric quality isopropyl alcohol and air drying in a dust free laminar flow hood although initial heating caused vaporization of the alcohol instant return of the surface charge and re attraction to the cavity walls heating above 600 u00b0 c neutralized the surface charge once again thermally neutralized sample alignment was restored and accurate u00b1 5.