volcanic tuff

And yet his music, to the end, although sometimes almost eerily serene, remained most often volcanic.
The Stacks: John Coltrane’s Mighty Musical Quest|Nat Hentoff|October 18, 2014|DAILY BEAST
This hidden Eden continues to baffle geologists with its oculus of volcanic stone.
What Made Mexico’s Most Mysterious Beach?|Brandon Presser|October 14, 2014|DAILY BEAST
But behold, DiCaprio, whose volcanic growth of furze is surely proof that the vogue for beards needs to be trimmed back.
Leo, the Beard Has to Go: When a Man’s Facial Hair Reaches Crisis Point|Tim Teeman|September 22, 2014|DAILY BEAST
Miles beneath the surface, in the absence of sunlight, animals derive energy from volcanic vents.
â€?Mission Blueâ€™ Warning: The Ocean Is Not Too Big to Fail|Sylvia A. Earle|August 15, 2014|DAILY BEAST

The largest of an archipelago of islands, Santorini is the vestige of a single volcanic landmass that erupted around 1600 BC.
Book a Room for Two in a Santorini Cave|Joanna Eede|June 10, 2014|DAILY BEAST
The volcanic eruptions of the mountains on the west broke down its barriers, and let its waters flow.
Blackwood's Edinburgh Magazine, Volume 60, No. 372, October 1846|Various
But scorn is far more volcanic than glacial and a poor barrier between sex and judgment.
Ancestors|Gertrude Atherton
Formosa, a large island in the Chinese sea, almost wholly inundated by volcanic agency, during a storm.
The Every Day Book of History and Chronology|Joel Munsell
It was probably at this volcanic ridge that the precipitous road obliged the mules to be sent back.
Life of Richard Trevithick, Volume II (of 2)|Francis Trevithick
It is divided throughout its whole extent by a chain of mountains, which in general owe their formation to volcanic eruptions.
Tobacco; Its History, Varieties, Culture, Manufacture and Commerce|E. R. Billings.