There are two artists with this name: a British progressive rock band and a goa psy trance group.
1) Quatermass was a British progressive rock band. Bridging progressive rock and hard rock in a hitherto unseen fashion, this power trio was notable for eschewing the seemingly requisite guitar of prog rock, relying instead on a heady fusion of organ and bass guitar as lead instruments. The only album released during the band's brief existence, the eponymous Quatermass (1970), is regarded as a prog classic, and today, original pressings command high prices.
Formed in London, England in September 1969, the trio consisted of John Gustafson (bass, lead vocals), Pete Robinson (keyboards), and Mick Underwood (drums), all notable names from earlier British music history, who had met while playing in Episode Six. The band's name was derived from the Quatermass science fiction serials produced by the BBC.
Their first single, "Black Sheep of the Family", showcased the group's hard-hitting sound, as well as Gustafson's throaty vocals. Their ground-breaking, heavily electronic sound them touted as a "band of the future" by media outlets of the period. Upon release, Quatermass, like other prog albums of the day, instantly garnered mostly negative criticism but was eventually vindicated by history. Despite a number of live performances, Quatermass quietly disbanded, partly as a result of disappointing sales.
Almost thirty years later, Quatermass was reformed as Quatermass II during the 1990s. The only band member retained from its earlier iteration was Underwood, though Gustafson did contribute a few songs. They released one album, Long Road (1997), before disbanding for a final time at the close of the millennium.
2) A goa psy trance group.