An endoprosthesis can include a body including an underlying portion and a surface portion overlying the underlying portion. The underlying portion can include a bioerodible metal in the form of a matrix and corrosion enhancing deposits within the matrix. The surface portion including the bioerodible metal of the matrix. The surface portion having a first erosion rate when exposed to a physiological environment and the underlying portion having a second erosion rate when exposed to a physiological environment that is greater than the first erosion rate.
