Maria was a brigantine of 136 tons, built in Dublin, Ireland, and launched in 1823 as a passenger ship.

Margaret Brock Reef is a reef in the Australian state of South Australia located in the state's coastal waters on its south-east coast about 7 kilometres (4.3 mi) west of the headland of Cape Jaffa and about 27.2 kilometres (16.9 mi) south-west of the town of Kingston SE. It is the site of both a navigation aid which operated as a staffed lighthouse from 1872 to 1973 and as an automatic beacon onward to the present day, and a rock lobster sanctuary declared under state law in 1973. It is named after the barque Margaret Brock which was wrecked there in 1852.