Besides
rare earths contained in monazite and zircon in the mineral sands,
Vietnam has large deposits of RE in carbonatites, discovered in the
late 1950s and located in the Fan Si Pan Mts., in the north of the
country. Three deposits were delineated: Mau Xe North and South and
Dong Pao. At Mau Xe, tabular or lense-form
orebodies are hosted in the Permo-Carboniferous
limestones. The mineralization is complex, consisting of bastnaesite,
parisite, uranopyrochlore, gadolinite, pyrite, apatite, and abundant
barite and fluorite. The weathered zone, to a depth of 20 m, contains
4-5% of RE oxides and the primary ore is averaging 1,4% REO (mainly
Ce, La, Nd, Pr, Y, but also Gd and Eu - 4% of REO), 1,1% Nb, 200-300
ppm U and 30% Ba. The reserves are huge; 7,8 Mt of REO, from which
1.7 Mt are proven,
at Mau Xe North alone. Dong Pao deposit, situated 40 km south
has about 7 Mt REO of a similar quality. It is hosted in a paleogene
syenitic intrusion .
The Dong
Pao mine is
one of the largest rare
earths mines
in Vietnam.The
mine is located in northern Vietnam
in
Lào
Cai Province and
has reserves amounting to 7 million tonnes of ore grading 5% RE.
The
Mau
Xe mine
has reserves amounting to 7.8 million tonnes of ore grading 4% RE.
Vietnam’s
rare earths production doubled from 2017 to 2018 to come in at 400
MT.
