Grenadier quartzite

This piece of quartzite is peculiar because of the presence of little round "pebbles" inside of it. On one hand it is possible that the metamorphic process that created this quartzite rock melted it so much that the minerals started to separate, or literally distill, out of the rock. This process forms banded gneiss. On the other hand, the pebbles in this rock look too round, graded, and stratified for me to be sure of the first possibility. Another possibility is that this is an old piece of conglomerate rock that was later welded together to form the hard quartzite. This process is strongly present to the far east, in the Sangre de Cristo Mountains. To imagine this process, think of a tranquil stream filled with pebbles, then buried in sand, and then welded together.