  Upon using fundamental electromagnetic properties of metasurfaces we build a
platform to classify reciprocal bianisotropic metasurfaces from typical
experimental measurements and determine isotropic, anisotropic, bi-isotropic
(chiral), and bianisotropic (so-called omega) properties. We provide
experimental guidelines to identify each class by measuring macroscopic
scattering parameters, i.e., reflection and transmission coefficients upon
plane wave illumination with linear and/or circular polarization. We explicitly
provide a recipe of what metasurface properties can and cannot be inferred by
means of chosen polarization, reflection, and transmission properties. We also
clarify common confusions in the classification of anisotropic versus chiral
metasurfaces based on circular dichroism measurements presented in the recent
literature.
