A rocks texture cannot be the sole determining factor in rock type identification. If the grains are loosely cemented and come off in your hands when you vigorously rub the rock, there's a good...
There are 2 or more very distinct gain sizes. The smaller grains are called phenocrysts and the material around it is called matrix or groundmass. The phenocrysts are 0.3 - 5 mm. To truly see what a...