铁石心肠

to have a heart of stone / hard-hearted / unfeeling

surname Tie

iron (metal) / arms / weapons / hard / strong / violent / unshakeable / determined / close / tight (slang)

iron and stone

surname Shi / abbr. for Shijiazhuang 石家莊|石家庄[Shi2 jia1 zhuang1]

dry measure for grain equal to ten dou 斗 / ten pecks / one hundred liters

rock / stone / stone inscription / one of the eight categories of ancient musical instruments 八音[ba1 yin1]

dry measure for grain equal to ten dou 斗[dou3]; one hundred liters / ancient pr. [shi2]

heart / mind / intention / center / core / CL:顆|颗[ke1],個|个[ge4]

heart / intention / one's inclination / state of mind / to have the heart for sth / mood

intestines

old variant of 腸|肠[chang2]