gneiss
non-foliated.
Gneiss
foliated
Metamorphic rocks with grains arranged randomly are said to be non-foliated. This means they do not have a layered or banded structure like foliated metamorphic rocks. Examples include marble and quartzite.
Metamorphic rocks without visible layering are typically formed under conditions of high temperature and pressure that cause the minerals within the rock to recrystallize. This may result in a homogeneous texture without distinct layers or bands. These rocks may still exhibit foliation or other textures that indicate their metamorphic origin, even if they lack visible layering.
Metamorphic rocks with a layered or banded look are referred to as foliated.
I dont know dude.
Foliated rocks have layers in them. We often refer to the layers as Banding.
Foliated metamorphic rocks have a layered or banded appearance due to alignment of mineral grains, exhibit strong cleavage, and are formed under directed pressure. Non-foliated metamorphic rocks do not have a layered structure, show more equidimensional mineral grains, lack cleavage, and are typically formed under contact metamorphism.
Not exactly. Some metamorphic rocks have foliation, which can appear similar to the layers of sedimentary rock. Foliation develops from mineral grains being oriented by pressure, rather than the deposition of layers.
Igneous rocks, such as granite and basalt, typically do not have layers because they form from the solidification of molten rock without the presence of bedding or foliation. These rocks cool and solidify quickly, preventing the development of distinct layers.
Metamorphic rocks that have a banded appearance due to the alignment of minerals are called foliated metamorphic rocks. This banding occurs as a result of directional pressure during metamorphism, causing the minerals to realign and form distinct layers or bands. Common examples of foliated metamorphic rocks include schist and gneiss.