George Mason was born in Peru in 1835. It is likely that he was mixed race.
Sources
1860 Census: "1860 United States Federal Census" The National Archives in Washington D.C.; Record Group: Records of the Bureau of the Census; Record Group Number: 29; Series Number: M653; Residence Date: 1860; Home in 1860: Bangor Ward 3, Penobscot, Maine; Roll: M653_447; Page: 117; Family History Library Film: 803447 Ancestry Sharing Link - Ancestry Record 7667 #44516010 George Mason (33), Mariner, in Bangor Ward 3, Penobscot, Maine. Born in Peru.
1870 Census: "1870 United States Federal Census" Year: 1870; Census Place: Bangor, Penobscot, Maine; Roll: M593_552; Page: 114A Ancestry Sharing Link - Ancestry Record 7163 #27202921 George Mason (35), Mariner, in Bangor, Penobscot, Maine. Born in Peru.