Flat White

The flat white zone is similar to the Blue Flat central area. Instead of being blue, main blocks are White. However, main differences are in the underground. There is much more mineral density of some kind in this zone than in the blue flat central area. And also at some deepness layers with a lot of carbon...
Of course, you'll have reach this zone to enjoy this advantage. Unfortunately for you, this zone is just after the huge blue mountain area...