Igneous Rock Textures
"There are
three main types of igneous
rock textures.."
Interlocking Texture
This is the largest group, called crystalline. The mineral crystals of those rocks have intelocked like in a jigsaw puzzle. There are three types of them: Phaneritic rocks have large grains that can be seen with bare eyes. Aphanitic rocks have fine grains which are too small to be seen without a hand lens or a microscope. Porphyritic rocks have two different sizes of minerals - large phenocrysts, and fine-grained matrix.
Crystalline texture of granite. By vidalia_11
Glassy Texture
The rocks in this group are called glassy because their matrix is glassy - they reflect light like glass, and often break like glass. Those rocks are either made of glass or tiny crystal surrounded by glass because the cooling has been extremely quick and minerals have had no time to grow.
Glassy texture of obsidian. By kevinzim
Fragmental Texture
The rocks in this group are called fragmental. They consist of igneous fragments such as mineral crystals, pieces of crystalline rock, or glass, that are cemented or packed together after they have solidified. They have often formed from volcanic ash and debris.
Fragmental texture of tuff. By only_point_five
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