In reference to crystals, twinning is the patterned intergrowth of two or more crystals grains in reversed or rotated position in relation to each other. Twinning adheres to a number of geometric relations and typically transpires from the commencement of crystal development. A wide variety of twinned crystal types occur comprised of many different substances. Included in this array are crystals of lanthanum aluminate, which are rarely formed perfectly on Earth. Instead, the substance characteristically exhibits stair-step twinning, which is a trait that interferes with the formation of confluent deposited thin-films. Lanthanum aluminate twinning is a significant problem since superconductors built on imperfect surfaces cannot handle higher levels of electric current and do not perform predictably.