The mathematical morphology is often reduced to the ordering construction and the structuring elements are limited to flat shapes. In this paper, exploiting the concept of convergence, we propose a color morphological formalism which allows bringing non-flat structuring element. Extending the mathematical morphology hit-or-miss transform to the color, we show that this formalism is adapted for complex color images, as skin images for dermatological purposes. We provide and comment results on synthetic and real images.