First and second hollow bodies each having at least one opening are joined by first forming a fracture zone in a joint region of the first body and then juxtaposing the bodies in a closed cavity of an internal high-pressure shaping tool with the second body spaced from and open toward the fracture zone of the first body. The composite includes a Spinel and a BGG glass bonded together and having transmission in the visible and mid-infrared wavelength region. When certain preferred salts are used, such as alkali metal carbonates, sulfur and halide species can be captured by the molten salt, thereby reducing SOx and HCl emissions. A method for matching impedances in a flip-chip circuit assembly may include providing a die having a first circuit, and forming a TSV over the die.