Blood Money (Ad-Diyat)
Bukhari :: Book 9 :: Volume 83 :: Hadith 41
Narrated Abu Huraira:
Two women from the tribe of Hudhail (fought with each other) and one of them threw (a stone at) the other, causing her to have a miscarriage and Allah's Apostle gave his verdict that the killer (of the fetus) should give a male or female slave (as a Diya).