A set of analytic forms provide empirical data used to determine the material properties of a part following its fabrication. Multiple of families of the forms are identically processed to provide a variety of data, including the reaction of the part material to compression, tension and bending stresses. The forms in each family have a structural feature that singularizes the directional effect of gravity on a test cross section of the material. The dimensions of the test cross section progressively vary within each family so that data can be generated for multiple levels of stress.