All SL(n) contravariant matrix-valued valuations on polytopes in
Rn are completely classified without any continuity assumptions.
Moreover, the symmetry assumption of matrices is removed. The general
Lutwak-Yang-Zhang matrix turns out to be the only such valuation if n≥4,
while a new function shows up in dimension three. In dimension two, the
classification corresponds to the known case of SL(2) equivariant
matrix-valued valuations