gasket will be used in the illustrated embodiment an axial spacing of approximately 0 058 u2033 allows the gasket to be used with planar corner shear joint types intended to provide a nominal gasket compression of 0 012 u2033 when completely assembled it should be appreciated that the corner shear joint mating features may be located at various recessed axial depths within the corresponding apparatus elements and the same one embodiment may be used with these different combinations the gasket 10 may be conveniently machined from solid stock such as round bar stock or tubing using a lathe or screw machine but other manufacturing processes such as stamping or coining in conjunction with appropriate annealing are also contemplated it will be apparent to practitioners that the benefits of sealing region protection and self centering may also be obtained with gaskets made by molding or machining polymer materials such as pfa but the resistance to diffusion of process fluid or contaminants will be reduced the round bar stock when used as presently preferred may be stainless steel or other suitable material such as hastelloy c276 or c22 as shown in fig3 a 3 d the inventive gasket 10 may be used with planar corner shear joint mating features similar to those disclosed in u s pat nos 5 803 507 or 6 394 138 wherein the inner raised lip 20 aligns the gasket 10 with a joint counterbore portion 320 and the outer raised lip 60 aligns the gasket 10 with a joint groove portion 360 when the joint is completely assembled a counterbore corner 322 shears into the.