The Felspathic Highlands Terrane (alternatively Feldspathic), or FHT, is composed predominantly of ancient anorthositic materials.  It has low iron oxide and thorium levels.  The FHT can be split into an inner and outer felspathic highlands.  The outer FHT has comparatively higher levels of iron oxide and thorium.  It is thought to be part of the FHT, with the differences being due to modification by ejecta from impacts in other terranes.  The FHT covers 65% of the lunar surface.
Overall, 6% of the lunar surface (and hence 9% of the FHT) consists of maria within the FHT, such as Mare Moscoviense.  FHT maria have on average only 2.2 ppm of thorium, which is twice as much as the lunar average but significantly less than the levels seen in the PKT maria.  Outer FHT non-maria regions contain 1 ppm of thorium, and only 0.3 ppm of thorium in the inner FHT.
The inner FHT lies exclusively in the far side of the Moon, whereas the outer FHT spans both sides and is the one of two terranes on the near side of the Moon, along with the PKT.  No spacecraft have landed on the inner FHT, as the only lander to the far side touched down in the South Pole-Aitken Terrane.  In contrast, the outer FHT has been the subject of human landings and sample return.