Abstract: Synthetic gemstones are produced by growing single crystals of silicon carbide, fashioning the silicon carbide into gemstone cores, and thereafter depositing a thin coating of diamond on the core.

Abstract: Raman-active optical fiber having very large Raman cross section is disclosed. The fiber comprises glass that has two major components, a glass-forming first component (GeO.sub.2, SiO.sub.2, AsO.sub.1.5, or combinations thereof) and a heavy metal oxide second component (PbO, BiO.sub.1.5, SbO.sub.1.5, TlO.sub.0.5, or combinations thereof), with the first and second major components making up at least 70 mol %, preferably at least 90 mol %, of the glass. The maximum relative Raman cross section .sigma..sub.r of the inventive glass is at least 15, preferably greater than 20, where .sigma..sub.r =.sigma..sub.RA /.theta..sub.SiO.sbsb.2, and where .sigma..sub.RA and .sigma..sub.SiO.sbsb.2 are the maximum 0.degree. K. Raman cross sections of the inventive glass and of pure vitreous SiO.sub.2, respectively.

Abstract: A glass reflow step to round off sharp edges of contact vias is typically included in processes for making integrated-circuit devices. In the course of making such devices with closely spaced vias, it has been found that unacceptable overhangs occur on the sidewalls of the vias. Neither changes in the composition of the glass nor modifications in the processing parameters of reflow were effective to avoid the overhang phenomenon. In accordance with the invention, it has been discovered that the overhang problem can be consistently avoided if the ratio of glass thickness to via-to-via spacing is about .ltoreq.0.393.

Abstract: Amorphous niobates and tantalates of the alkali metals lithium, potassium, and sodium which may be off-stoichiometric with regard to the related octahedrally coordinated crystalline compositions manifest high values of dielectric constant and ionic conductivity. Electrode bearing devices may be utilized, inter alia, as capacitors, electrolytic cells, and bolometers.