Abstract: A fluorescent lamp can incorporate a new strontium-calcium fluorapatite of the formulaCa.sub.5.0-a-w-x-y Sr.sub.a Cd.sub.w Mn.sub.x Sb.sub.y (PO.sub.4).sub.3 F.sub.1-y O.sub.ywhereina is from about 0.25 to about 4.75-w-x-yw is from 0 to about 0.2x is from about 0.05 to about 0.5y is from about 0.02 to about 0.2The compositions have unexpected chromaticity properties.

Abstract: A fluorescent lamps having chromaticity coordinates similar to cool white can be prepared using two component compositions. A blue emitting strontium-barium chlorapatite activated with europium and a yellow emitting calcium-strontium fluorapatite applied as a blend or as two distinct layers yields a lamp equivalent in chromaticity to a standard cool white lamp with a higher lumer per watt than the standard cool white lamp.

Abstract: Fluorescent lamps containing a two-component phosphor system consisting essentially of europium activated barium magnesium aluminate as a blue emitter and manganese and antimony activated calcium chlorofluorapatite as a yellow emitter use less energy to achieve at least comparable brightness as a standard cool white lamp with a suitable color rendering index.

Abstract: Improved fluorescent efficiency is achieved by a luminescent composition consisting essentially of from about 99.97% to about 99.995% by weight of a manganese-activated magnesium aluminum gallate phosphor having the formula:Mg.sub.a Mn.sub.b Ga.sub.2.sub.-c Al.sub.c O.sub.(3.sub.+a.sub.+b)wherein a + b is from about 0.85 to about 1.05, b is from about 0.001 to about 0.06, c is from about 0.01 to about 1.2 and as a stabilizer from about 0.005% to about 0.03% by weight of cerium. The lamps employing such luminsecent compositions have improved fluorescent efficiency, lamp life and lamp operating maintenance as compared to materials without the cerium stabilizer.

Abstract: Increased luminescence intensity in magnesium aluminum gallate phosphors as well as magnesium gallate phosphors is achieved by utilizing a fluorine source in the raw material mix and by conducting initial processing in a humid, oxidizing atmosphere. Additionally, processing time is drastically reduced.