High Tide - Sea Shanties (1969) (prog/psych/proto-metal)
One of the first rock albums to incorporate violin...
https://en.wikipedia.org/wiki/Sea_Shanties_(High_Tide_album)
"On Sea Shanties, there's nothing fey and flowery in Hill's bleak lyrics or his doomy
Jim Morrison-like delivery, and psychedelia's melodic whimsy is supplanted by a physicality more in line with the visceral heft of metal progenitors...High Tide weren't a power trio, though, and it was the interplay of Hill's guitar with Simon House's violin that created the band's unique signature. Showing that rock violin needn't be a marginal adornment, House whips up an aggressive edge that rivals the guitar... High Tide had the muscularity of a no-nonsense proto-metal band, but they also ventured into prog territory with changing time signatures and tempos, soft-hard dynamics, multi-part arrangements, and even some ornate faux-Baroque interludes... Far from the collection of nautical ditties its name suggests, Sea Shanties is an overlooked gem encapsulating the shifting musical currents in late-'60s British rock."
