Lock is significant in Australian history due to her educational achievements, having the first legally recognised marriage between a settler and an Aboriginal person, and later for being a landowner in early colonial times.
The achievement of a black girl, aged 14, believed to be Maria Lock, winning first prize in a NSW examination ahead of approximately 120 other students was reported in the Sydney Gazette on 17 April 1819.
That same year Lock, living with the Hassall family, married Thomas Walker "Dickey" Coke, a son of Bennelong, who had also been in the Native Institution.
[3] However, the facts of her employment within the Hassall household and marriage to Dickey are in contention, as information in her later petition for land states that she continued in the Native Institution school until she was married to Robert Lock.
40 acres were granted to Robert on Maria's behalf, but Cartwright frustrated this claim as he felt it was injurious to the established buildings on his adjoining allotment.
Dozens of families continue to trace their ancestry through Maria, her father Yarramundi and her grandfather Gomebeeree, stretching back to the 1740s.