Chant's first novel was Red Moon and Black Mountain, a parallel world fiction. According to the author, it was based on elaborate fantasy legends and imaginary games she began enacting and writing as a young child. It was first published in England by George Allen & Unwin in 1970, and in 1971 in the America by Ballantine Books as part of the celebrated Ballantine Adult Fantasy series, with a cover by illustrator Bob Pepper. The "House of Kendreth" sequence includes this novel and Chant's subsequent books The Grey Mane of Morning (1977) and When Voiha Wakes (1983).
Chant's other major work is The High Kings (1983), illustrated by George Sharp, designed by David Larkin and edited by Ian and Betty Ballantine. It is a reference work on the King Arthur legends and the Matter of Britain incorporating retellings of the legends. She has also written numerous articles on fantasy fiction.
Red Moon and Black Mountain won the Mythopoeic Fantasy Award in 1972; The Grey Mane of Morning was a runner for the same award in 1981, with tenth place in the Locus Poll Award the same year; When Voiha Wakes won the Mythopoeic Fantasy Award in 1984. The High Kings, which took second place in the Locus Poll Award, won the 1984 World Fantasy Special Award for Professional Work. It was also a nominee of the Hugo Award for Best Non-Fiction Book.