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Thesis (Ph. D.)--University of Michigan, 1925. / Cover title. "Reprinted from the Journal of the American ceramic society, vol. 8, no. 7. July. 1925." Bibliography: p. 428-429.

The utilization of the expansion accompanying kyanite’s inversion in the production of a dry pressed refractory insulating material has been studied quantitatively with respect to: (1) clay-kyanite-combustible ratio; (2) addition of fluxing and mineralizing materials; (3) variation in forming pressure; (4) variation in grain size of kyanite content; (5) effect of heat treatment; and (6) effect of forming characteristics on fire properties. The resilient property of combustible-containing bodies has been controlled by small additions of bentonite or sodium aluminate. The disruption of the structure of the body during the kyanite’s inversion reaction has been controlled by small additions of Virginia apatite and sodium aluminate and proper heat treatment. Indicative results show that it is possible to produce a dry pressed insulating refractory body from a 3:1:1 ratio of 35 mesh kyanite to clay to combustible which exhibits excellent dry properties, fired properties which comply with A S T W specifications of bulk density and volume stability, and cold crushing strength only slightly less than commercial grades of insulating refractories recommended for service at 2900-3000℉. / M.S.

Master of Science

This kyanite quartzite deposits at Leigh, Baker and Willis Mountains located in the south central Virginia Piedmont were investigated to determine their genesis, extent, and geologic and petrographic character. Kyanite quartzite in Virginia typically contains 20-40 per cent kyanite, 0-5 per cent pyrite, 0.5-1.5 per cent rutile, a per cent or so of mica or clay with the balance quartz. They occur as single beds within metamorphic rocks ranging from slates and phyllites of the greenschist facies south of Leigh Mountain, to schists and gneisses of the amphibolite facies at Baker and Willis Mountains. Post-kyanite hydrothermal alteration along fractures has altered large segments of the Baker Mountain deposit to clay and topaz. The protolith of kyanite quartzite is believed to have been extraordinarily pure mixture of quartz and kaolinite which was produced by either Iateritic weathering or by circulating meteoric waters. Isochemical regional metamorphism is believed to have occurred in a high pressure, moderate temperature environment in which water was either deficient or able to escape. Fluorine may have had a catalytic effect in promoting kyanite crystallization. No evidence was found of hydrothermal introduction of alumina, or localization of kyanite as a result of differential stress. The rocks enclosing kyanite quartzite in the Leigh Mountain area are believed to be basal members of the lower Paleozoic (?) Volcanic-Slate series. The gneisses surrounding Willis and Baker Mountains may be more highly metamorphosed, infolded remnants of the same series. The kyanite deposits of Virginia are extensive and well situated for mining. Possible reserves of kyanite quartzite containing over 25 per cent kyanite available for open pit mining are measured in tens of millions of tons.

Conditions of 8kb and 800°C are estimated for sillimanite K feldspar bearing metapelites and garnet-clinopyroxene bearing amnphibolites in Glen Muick. These conditions are inconsistent with the simultaneous nearby presence of equilibrium between andalusite and kyanite. Andalusite in the Glen Muick area is late. The sillimanite zone may have been in part primary. There is a transition without major structural break between Tay Nappe flat belt and the "Banff Nappe". A dataset has been derived for phases in the system KCMASHCO₂. The MHSRK equation of Kerrick and Jacobs (1981) has been used to extract data from mixed devolatilisation equilibria. Heats of formation are in agreement with calorimetrically determined values. Phlogopite equilibria calculated using disordered phlogopite data seem most appropriate to natural metapelite assemblages. Variations in pressure and temperature have been constrained across the Dalradian using various calibrated reactions. Temperatures vary from about 500°C in the low kyanite zone to 800°C in the sillimanite-K feldspar zone and pressures vary from 4kb to 10kb. Pressure estimates are justified on the basis that they are consistent with the aluminosilicate phase diagram. Rocks from the Central Highlands to Glen Clova underwent a decrease in pressure during evolution through peak metamorphic conditions. Amphibolites from the southern Moines show evidence of a former eclogitic assemblage of early Grampian age or earlier. High temperature regional metamorphic rocks lie at high structural levels and are are suggested to be an allochthonous unit, the Banff Nappe of Grampian age. The western margin of the Banff Nappe is marked by a temperature maximum to the immediate east, sharp thermal transitions, a train of metabasites and a high strain zone. It is suggested that emplacement of a Banff Nappe resulted in the deformation and metamorphism of structurally lower rocks.