RT Journal Article SR Electronic T1 Melting reactions in the system KAlSi 3 O 8 -SiO 2 -H 2 O to 18.5 kilobars JF American Journal of Science JO Am J Sci FD American Journal of Science SP 609 OP 626 DO 10.2475/ajs.267.5.609 VO 267 IS 5 A1 I. B. Lambert A1 J. K. Robertson A1 P. J. Wyllie YR 1969 UL http://www.ajsonline.org/content/267/5/609.abstract AB Synthetic sanidine and a sanidine-natural quartz mixture were reacted with 30 to 40 percent water and the melting relations were determined to 18.5 kb. The divariant melting intervals located for each sample, along with the results of previous studies in the system, provided good estimates of the position of the univariant curves for the two reactions Or + V <--> L, and Or + Qz + V <--> L. Muscovite was present in trace amounts in all runs, including those quenched from the conditions well above its maximum T stability limit, but it was not found enclosed in glass. Thus, the muscovite was deposited from the vapor phase. Schematic phase diagrams for the system indicate that muscovite would not be expected as a stable liquidus phase for mixtures on the join KAlSi 3 O 8 -SiO 2 -H 2 O at pressures less than 10 kb.