Tuff is formed from pyroclastic flows and usually consists largely of ash. Pumice is a vesicular rock formed when bubbles are trapped in solidifying, airborne lava.
== == Rhyolite, basalt, pumice, obsidian, andesite, dacite, tuff, welded tuff, scoria.
some examples of igneous rocks are granite,basalt,and rhyolite and driolite
Obsidian is a dense, dark volcanic rock formed from fast-cooling lava, resulting in a glassy texture, while pumice is a light, porous volcanic rock formed from frothy lava with trapped air bubbles, giving it a spongy texture. Obsidian is typically black or dark-colored, while pumice is usually light-colored due to its high porosity.
Pumice is more related to a textural feature, rather than a compositional attribute. For example, pumice originates when there are enough dissolved gases in the magma, such that when it is ejected from the volcano, the depressurization of the dissolved gases causes a rapid expansion as the gases exsolve (just like when you open a pop - the gases are initially under pressure, and you release that pressure by opening the can or bottle). The rapid change in temperature, from hundreds to thousands of degrees to the temperature of of the surrounding environment, causes a rapid cooling effect, whereby the expanding gases are frozen in place. These two factors are what give pumice its distinctive texture and ability to float when placed in water, as opposed to other volcanic rocks (such as scoria).Whether or not the pumice is felsic (light in color) or mafic (dark in color) depends on its chemical composition and therefore, pumice can be both felsic or mafic depending on its parental magma.General classification as to whether a rock is felsic or mafic is with regards to the silicate content of the rock as follows:felsic < 69% SiO2Intermediate Felsic 63 - 69% SiO2Intermediate 52- 63% SiO2Mafic < 52% SiO2Ultra Mafic < SiO2This said, felsic pumice (white or light tan brown colors) are more common to find than mafic pumice.
One characteristic that can help distinguish between sandstone and tuff is their composition. Sandstone is primarily composed of sand-sized mineral grains cemented together, while tuff is composed of volcanic ash and tephra fragments that have been compacted and cemented together. Tuff may also exhibit a finer texture due to the smaller size of volcanic particles compared to sand grains in sandstone.
Squashed pumice blobs in a welded tuff .
Pumice and tuff are the product of violent eruptions. Rhyolite is often, but not always produced by violent eruptions, but it can also form from slow, extrusive eruptions.
== == Rhyolite, basalt, pumice, obsidian, andesite, dacite, tuff, welded tuff, scoria.
== == Rhyolite, basalt, pumice, obsidian, andesite, dacite, tuff, welded tuff, scoria.
Basalt, Andesite, Rhyolite, Obsidian, Pumice, Tuff, Ash (Lava).
Explosive volcanoes can produce pumice and tuff.
Explosive eruptions will produce pyroclastic rocks such as scoria, pumice, and tuff.
Rocks unique to volcanoes include basalt, andesite, rhyolite, scoria, pumice, and tuff.
Tough is the same as rough; tuff means cool (ex:a tuff looking Mustang or a tuff record)
Sandstone is a sedimentary rock formed when sand weathered from preexisting rock is cemented together. Tuff is an igneous rock formed from volcanic ash.
obsidian,basalt,granite,pumice,tuff,diorite,gabbro,andesite,ect
When volcanic ash compacts, it creates a rock called Tuff. Tuff is sometimes called tufa when used in construction materials.