One of the subjects of the invention is a neodymium hydroxynitrate corresponding to the following formula: Nd(OH)x(NO3)Y.zH2O (I> in which: - 2.3 </= x </= 2.7 - 0.3 </= y </= 0.7 - 1.5 </= z </= 2.2. Another subject of the invention is the neodymium hydroxynitrate prepared by dehydration of the neodymium hydroxynitrate of formula (I). The invention is also targeted at the processes for the manufacture of the abovementioned neodymium hydroxynitrates and their applications as intermediates in the manufacture of neodymium oxide.
