Lewisian Gneiss Rock, Isle of Lewis -the Geology of the Outer Hebrides is important - as the predominant rock type is a Lewisian Gneiss - a metamorphic rock which is astonishingly up to 3 billion years old, making it the oldest rock in Britain - two thirds the age of the Earth.
Disharmonic folds in gneiss. Gneiss is a common and widely distributed type of rock formed by high-grade regional metamorphic processes from pre-existing formations that were originally either igneous or sedimentary rocks.
Blue Tigers Eye. Tiger's eye is a chatoyant gemstone that is usually a metamorphic rock that is a golden-brown to red-brown color, w/ a silky luster. A member of the quartz group, it is a classic example of pseudomorphous replacement by silica of fibrous crocidolite (blue asbestos)