We adopted Rodriguez-Frank orientation space for description of {10-12} twin variants, sorted by increasing Schmid factor values. In the examined examples we distinguished three pairs of those variants (1+2, 3+4 and 5+6) as the SF values were very similar for those pairs. The representation of those pairs of variants in the above mentioned orientation space, suggest that they form three disjunctive sets of orientations. But this hypothesis is not true, because the matrices orientations closer to origin of coordinate system cause twin variants overlapping. Though this kind of analysis can be helpful in qualitative validation of obeying Schmid law in twin variant selection.