Recent work by GEUS shows that the source rocks contain two types of ilmenite and very little magnetite. Ilmenite crystallised as a primary phase in basaltic hosts but formed also by exsolution in primary and titanium-rich magnetite. In the host rocks, the remaining and titanium-depleted magnetite recrystallised in iron-bearing silicate minerals and left ilmenite behind. Host rocks were subsequently eroded and ilmenite was easily separated from less dense silicate minerals and concentrated into the ilmenite sand in the dynamic environment along the seashore.
Our recent and historical work, comprising on- and offshore geological and geophysical surveys, photogrammetry, and petrographic and mineralogical analyses is helping industry to advance exploration projects focused on the placer deposits.