Affiliation: | 1. Electrotechnical Laboratory Norris, Tennessee;2. Electrotechnical Laboratory Norris, Tennessee
The authors are, respectively, senior mineralogist, Southern Experiment Station, in charge of the refractories section at Norris, Tenn., and supervising engineer, Electrotechnical Laboratory, Bureau of Mines, U. S. Department of the Interior, Norris, Tenn. |
Abstract: | The massive kyanite of Georgia is similar in structure to India kyanite, but it contains quartz with only occasional small amounts of corundum; sericite between the kyanite crystals is common. Excellent coarse grog (67% through 6- on 35-mesh) can be produced from this kyanite. Maximum expansion of the rock during calcining occurs at 1400°C. with slight shrinkage thereafter. Brick were made of the kyanite grog with 3% and 10%, respectively, of EPK (Florida) clay; both had excellent resistance to load at elevated temperatures and met the reheat specifications of the Navy Department and the A.S.T.M. In the panel spalling test, Georgia kyanite brick showed approximately 20% loss, whereas India kyanite brick of the same grain size and clay content showed only 0.3% loss. Intensive prospecting is necessary and the unusual mining and cleaning operations with present known deposits make large-scale commercial operation questionable. |