In geology, a metamorphic zone developed in the contact area around igneous rock intrusions when carbonate sedimentary rocks are invaded by and replaced with chemical elements that originate from the igneous rock mass nearby.
Many skarns also include ore minerals; productive deposits of copper or other base metals have been found in and adjacent to skarns. The typical rock of a skarn is hornfels, a fine-grained, flinty rock produced by the heat and solutions given off by the intruding magma.