Let $T$ be a $d$-dimensional simplex in a $d$-dimensional real
normed space ($=$ Minkowski space). We introduce a special
Minkowskian area-measure and Minkowskian trilinear coordinates
with respect to $T,$ allowing us to study Minkowskian balls which are tangent to all hyperplanes determined by the facets of $T.$ Finally we apply the derived statements to characterize simplices having special Minkowskian properties, namely simplices with equal Minkowskian heights and simplices with medians of the same Minkowskian length.