During the final stages of cooling of a water-rich magma, crystals can often rapidly grow to very large sizes, producing a very coarse-grained rock within which all crystals are at least 1 cm or larger in size. what do we call the igneous texture with such extremely large crystals?

during volcanic eruptions some magmas, particularly very viscous ones, cool so rapidly that there is no time to form even tiny crystals. the lava solidifies into a mass of glass and produces a texture.

if a volcano erupts explosively, material is violently ejected onto the surrounding landscape, producing rocks that consist of broken fragments of rock, mineral crystals, and glass instead of tightly interlocking crystals. what is such a fragmental igneous texture called?

some lavas contain significant amounts of gases that can become trapped in the rock as the lava solidifies. this can produce an extrusive rock that contains numerous round holes, giving the rock the appearance of swiss cheese or a sponge. what do we call such a porous igneous texture?