Method of making crystalline mica bodies and products

Claim 1

THE METHOD OF PRODUCING SUBSTANTIALLY CRYSTALLINE BODIES GREATER THAN ABOUT 600 CC. BUT LESS THAN ABOUT 1000 CC. IN VOLUME OF SYNTHETIC FLUOROPHLOGOPITE MICA HAVING EXCELLENT ELECTRICAL AND MACHINING PROPERTIES AND HAVING NO INTERNAL VOIDS OR SURFACE DEFECTS COMPRISING MELTING A BATCH CONTAINING THE CONSTITUENTS OF FLUOROPHLOGOPITE MICA, HAVING THE FORMULA KMG3ALSI3O10F2, SAID CONSTITUENTS BEING PRESENT IN SUCH PROPORTIONS THAT SAID MELT IS STOICHIOMETRICALLY EQUIVALENT TO AT LEAST ABOUT 90% BY WEIGHT FLUOROPHLOGOPITE, ABOUT 0.2-10.0% BY WEIGHT OF CHROMIUM OXIDE AS A NUCLEATING AGENT, AND AT LEAST ONE POLYVALENT METAL ION OF THE GROUP CONSISTING OF CU2+, SN4+, TI4+, ZR4+, MN4+, ZN2+, AND MO6+ WHICH IS SUBSTITUTED FOR THE MAGNESIUM ION OF THE FLUOROPHLOGOPITE ON A MOLE FOR THE MOLE BASIS, IN AN AMOUNT FROM 0.005-0.1 TOTAL MOLE, PASSING THE MOLTEN BATCH TO FORMING MEANS, THE SURFACE OF WHICH IS HEAT-CONDUCTIVE, THEREBY SIMULTANEOUSLY FORMING THE MOLTEN BATCH INTO THE DESIRED SHAPE AND RAPIDLY CHILLING THE SURFACE OF SAID SHAPE TO A TEMPERATURE AT LEAST BELOW THE SOFTENING POINT OF THE MELT, MAINTAINING THEREAT FOR ABOUT 10 TO 60 SECONDS TO FORM A GLASS SURFACE LAYER THEREON, BUT RETAINING THE INTERIOR IN THE MOLTEN STATE, AND THEREAFTER IMMEDIATELY REMOVING SAID SHAPE FROM THE FORMING MEANS AND ANNEALING SAID SHAPE TO CAUSE FLUOROPHLOGOPITE MICA CRYSTALS TO GROW PERPENDICULARLY FROM THE SURFACE LAYER INWARD.

Claim 2

THE METHOD OF PRODUCING SUBSTANTIALLY CRYSTALLINE BODIES GREATER THAN ABOUT 600 CC. BUT LESS THAN ABOUT 1000 CC. IN VOLUME OF SYNTHETIC FLUOROPHLOGOPITE MICA HAVING EXCELLENT ELECTRICAL AND MACHINING PROPERTIES AND HAVING NO INTERNAL VOIDS OR SURFACE DEFECTS COMPRISING MELTING A BATCH CONTAINING THE CONSTITUENTS OF FLUOROPHLOGOPITE MICA, HAVING THE FORMULA KMG3ALSI3O10F2, SAID CONSTITUENTS BEING PRESENT IN SUCH PROPORTIONS THAT SAID MELT IS STOICHIOMETRICALLY EQUIVALENT TO AT LEAST ABOUT 90% BY WEIGHT FLUOROPHLOGOPITE, ABOUT 0.2-10.0% BY WEIGHT OF CHROMIUM OXIDE AS A NUCLEATING AGENT, AND AT LEAST ONE POLYVALENT METAL ION OF THE GROUP CONSISTING OF CU2+, SN4+, TI4+, ZR4+, MN4+, ZN2+, AND MO6+ WHICH IS SUBSTITUTED FOR THE MAGNESIUM ION OF THE FLUOROPHLOGOPITE ON A MOLE FOR THE MOLE BASIS, IN AN AMOUNT FROM 0.005-0.1 TOTAL MOLE, PASSING THE MOLTEN BATCH TO FORMING MEANS, THE SURFACE OF WHICH IS HEAT-CONDUCTIVE, THEREBY SIMULTANEOUSLY FORMING THE MOLTEN BATCH INTO THE DESIRED SHAPE AND RAPIDLY CHILLING THE SURFACE OF SAID SHAPE TO A TEMPERATURE AT LEAST BELOW THE SOFTENING POINT OF THE MELT, MAINTAINING THEREAT FOR ABOUT 10 TO 60 SECONDS TO FORM A GLASS SURFACE LAYER THEREON, BUT RETAINING THE INTERIOR IN THE MOLTEN STATE, AND THEREAFTER IMMEDIATELY REMOVING SAID SHAPE FROM THE FORMING MEANS AND ANNEALING SAID SHAPE TO CAUSE FLUOROPHLOGOPITE MICA CRYSTALS TO GROW PERPENDICULARLY FROM THE SURFACE LAYER INWARD.