In the transition zone, water is carried by wadsleyite and ringwoodite; in the relatively cold conditions of a descending slab, they can carry up to 3 wt%, while in the warmer temperatures of the surrounding mantle their storage capacity is about 0.5 wt%.[14] The transition zone is also composed of at least 40% majorite, a high pressure phase of garnet;[15] this only has capacity of 0.1 wt% or less.[16]