Gneiss is often the first major league ore that up and coming miners graduate to. Finding the more II-Grade variation of Gneiss, known as iridescent gneiss, is a major coup for these miners due to its 5% greater mineral yield. Gneiss is a popular ore type because it holds significant volumes of three heavily used minerals, increasing its utility value. It has quite a bit of Mexallon as well as some Pyerite and Isogen. This material was compressed using an older process that compressed batches of raw materials into units using a set input quantity. Newer compression technology uses a more flexible one-to-one unit compression system.