What Type Of Rock Is The Oldest Metimorfic Igneous Or Sedimantary?

Metamorphic rocks are generally considered the oldest type of rock because they form from the alteration of existing rocks—either igneous, sedimentary, or even older metamorphic rocks—under heat and pressure. While igneous and sedimentary rocks can also be ancient, the processes that form metamorphic rocks often involve these older types. Therefore, in terms of geological history, metamorphic rocks can be older than both igneous and sedimentary rocks.