Hattori's research interest has also extended to porphyry-type deposits, which supply critical metals such as copper, molybdenum, and gold. Through her research, she presented evidence supporting the notion that sulfur and metals have their origin in the mantle, and proposed that they were extracted and transported by mafic magmas from the mantle to shallow crustal levels. This proposal was based on her earlier work on Pinatubo eruption products, where metals and sulphur are released from mafic magmas during their ascent and incorporated into overlying erupted felsic magmas. Furthermore, Cees-Jan DeHoog, her post-doctoral research fellow, provided evidence that oxidized magmas are capable to transport metals and sulphur from deep in the mantle to shallow levels of crust.