Abstract: A subcutaneous cavity marking device percutaneously implantable in breast tissue during a biopsy procedure. The marking device including at least two implantable bodies, one made from a first material and another made from a second material wherein the first and second materials are different materials and the at least two implantable bodies are adapted to be inserted into a subcutaneous cavity created by removal of tissue. The at least two implantable bodies are detectable via non-invasive techniques as tissue cavity markers and at least one of the at least two detectable bodies is an electronic chip connected to the other of the at least two implantable bodies.