The Lewisian Complex (Scotland) is Archean continental crust (2.7-3 billion years old) which has undergone repeated deformation and metamorphism. The original rock was likely granitic (TTG suite) but this specimen has been extensively deformed and altered and fractured and recemented, giving it this brecciated look. Fig 1 and 2 show angular fragments of likely garnet, quartz, a fine grained green phase (maybe epidote--its nearly as hard as qz), and a mafic phase (biotite or Hbl or pyroxene--I can't tell). Fig 3 shows the green material likely filling in cracks via metasomatism (fluid based chemical changes). Fig 4 shows quartz bordering the green altered minerals. Fig 4 shows the green material working its way around and into the garnet.

The rock is chaotic, and I think spectacular. Mineral identifications are the best I can do without thin section or more advanced techniques.