Are metamorphic rocks the oldest?

Sedimentary rocks, such as sandstone, are created by the compression of sediment or particles. Metamorphic rocks are formed when existing igneous or sedimentary rocks are fused together by high heat and pressure. Finding the oldest rocks in the world is a harder task than it might seem. read more

The oldest rocks in Britain are found in NW Scotland and the western isles. This ancient Lewisian gneiss is almost 3,000 million years old! The Scottish Highlands are mainly formed from metamorphic rocks formed around 400-450 million years ago. read more

Metamorphic rocks are those which A) are claimed to have certain metaphysical properties, e.g., quartz crystals. B) have mineral compositions altered from those originally present by increased temperature and pressure. C) have textures altered from those originally present by agents such as water and volatile magmatic fluids. read more