other combinations as would be known by one skilled in the art in the case of certain precursor options particularly with powders they can be compressed before heat treatment at 550 u00b0 900 u00b0 c for 1 1200 minutes and in a preferred embodiment for 650 u00b0 c for approximately 20 minutes the compression may be accomplished with a threaded cap and or a keyed plunger and a spanner wrench is a common tool to tighten such large diameter thin caps the bottom of the cavity may have a second opening sealed by a second cap with such design being intended to simplify formation of the block the use of powder precursor raises the problem that compression can create cracks in the mgb 2 filaments that the powder cannot infiltrate and bridge to ensure electrical connectivity this problem may be solved in another embodiment by the use of a sol gel form of mgb 2 which in its liquid form can infiltrate as well as surround the mgb 2 wire ends the sol gel precursors may be poured into the block and first heat treated at a low heat to evaporate the liquid compounds as would be known by one skilled in the art and then subsequently heat treated at a higher heat and longer time which one skilled in the art would know to be at 550 u00b0 900 u00b0 c for 1 1200.