Tuff (from the Italian tufo) is a type of rock made of volcanic ash ejected from a vent during a volcanic eruption. source
Tuff (from the Italian tufo) is a type of rock made of volcanic ash ejected from a vent during a volcanic eruption.
Tuff is sometimes called tufa, particularly when used as construction material, although tufa also refers to a quite different rock. source
Tuff is sometimes called tufa, particularly when used as construction material, although tufa also refers to a quite different rock.
Rock that contains greater than 50% tuff is considered tuffaceous. source
Rock that contains greater than 50% tuff is considered tuffaceous.
Tuff is a relatively soft rock, so it has been used for construction since ancient times. source
Tuff is a relatively soft rock, so it has been used for construction since ancient times.
Tuff is common in Italy the Romans used it often for construction. source
Tuff is common in Italy the Romans used it often for construction.
The Rapa Nui people used Tuff to make most of the moai statues in Easter Island. source
The Rapa Nui people used Tuff to make most of the moai statues in Easter Island.
Tuff can be classified as either sedimentary or igneous rocks. source
Tuff can be classified as either sedimentary or igneous rocks.
Tuff are usually studied in the context of igneous petrology, although they are sometimes described using sedimentological terms. source
Tuff are usually studied in the context of igneous petrology, although they are sometimes described using sedimentological terms.
Welded tuff is a pyroclastic rock, of any origin, that was sufficiently hot at the time of deposition to weld together. source
Welded tuff is a pyroclastic rock, of any origin, that was sufficiently hot at the time of deposition to weld together.
The Lava Creek Tuff erupted from Yellowstone Caldera in Wyoming 640,000 years ago. source
The Lava Creek Tuff erupted from Yellowstone Caldera in Wyoming 640,000 years ago.
Lava Creek Tuff is known to be at least 1000 times as large as the deposits of the May 18, 1980 eruption of Mount St. Helens. source
Lava Creek Tuff is known to be at least 1000 times as large as the deposits of the May 18, 1980 eruption of Mount St. Helens.
Trachyte tuffs contain little or no quartz but much sanidine or anorthoclase. source
Trachyte tuffs contain little or no quartz but much sanidine or anorthoclase.
Recent trachyte tuffs are found on the Rhine (at Siebengebirge), in Ischia, near Naples, Hungary, etc. source
Recent trachyte tuffs are found on the Rhine (at Siebengebirge), in Ischia, near Naples, Hungary, etc.
Ultramafic tuffs are extremely rare; their characteristic is the abundance of olivine or serpentine and the scarcity or absence of feldspar and quartz. source
Ultramafic tuffs are extremely rare; their characteristic is the abundance of olivine or serpentine and the scarcity or absence of feldspar and quartz.
Basaltic tuffs are also of widespread occurrence both in districts where volcanoes are now active and in lands where eruptions have long since ended. source
Basaltic tuffs are also of widespread occurrence both in districts where volcanoes are now active and in lands where eruptions have long since ended.