Final answer:
Sedimentary rocks can have textures ranging from coarse-grained with visible minerals to fine-grained with minerals too small to see without magnification. Sandstone is a type of clastic sedimentary rock, while non-foliated metamorphic rocks appear massive and lack any mineral alignment.
Step-by-step explanation:
The texture characterized by discrete grains of rock, minerals, or fossils, which is predominantly seen in sedimentary rocks, reflects the physical appearance and feel of the rock's surface. Sedimentary rocks often exhibit a variety of textures, one of which is a coarse-grained texture where the grains or crystals are easily discernible to the nak-ed eye. These grains are typically larger than 1 millimeter and the mineral constituents are identifiable. In contrast, extremely fine-grained sedimentary rocks contain minerals, such as clay minerals, that are too small to see without magnification, manifesting as dark-colored rocks with noticeable bedding but no visible detail at the scale of hand-lens.
Sandstone is an example of a clastic sedimentary rock composed of sand-sized minerals and rock fragments. The texture, size, shape, and composition of a sedimentary rock can often provide insights into its formation, including the conditions of the environment where it was deposited. On the other hand, non-foliated metamorphic rocks do not show any alignment of mineral crystals, making them appear massive and structureless.