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Monazite. Monazite is a primarily reddish-brown phosphate mineral that contains rare-earth elements. Due to variability in composition, monazite is considered a group of minerals. [3] The most common species of the group is monazite- (Ce), that is, the cerium-dominant member of the group. [4] It occurs usually in small isolated crystals.
The lanthanide (/ ˈ l æ n θ ə n aɪ d /) or ... Monazite is a phosphate of numerous group 3 + lanthanide + actinide metals and mined especially for the thorium ...
Monazite (marine sands from Brazil, India, or Australia; rock from South Africa), bastnäsite (from Mountain Pass rare earth mine, or several localities in China), and loparite (Kola Peninsula, Russia) have been the principal ores of cerium and the light lanthanides. [36]
The composition of the lanthanides was about 49% cerium, 33% lanthanum, 12% neodymium, and 5% praseodymium, with some samarium and gadolinium, or distinctly more lanthanum and less neodymium and heavies as compared to commercial monazite. The europium content was at least double that of a typical monazite.
Lanthanum. Lanthanum is a chemical element; it has symbol La and atomic number 57. It is a soft, ductile, silvery-white metal that tarnishes slowly when exposed to air. It is the eponym of the lanthanide series, a group of 15 similar elements between lanthanum and lutetium in the periodic table, of which lanthanum is the first and the prototype.
Monazite is a waxy mineral that is formed through the crystallization of igneous rocks and the metamorphism of clastic sedimentary rocks. [25] This mineral is typically mined in placer deposits, with gold commonly found as a byproduct. [25] The rare earth element neodymium is found in monazite, making it a rare mineral. [25]
Cerium occurs in various minerals, but the most important commercial sources are the minerals of the monazite and bastnäsite groups, where it makes up about half of the lanthanide content. Monazite-(Ce) is the most common representative of the monazites, with "-Ce" being the Levinson suffix informing on the dominance of the particular REE ...
Lanthanites are a group of isostructural rare earth element (REE) carbonate minerals. This group comprises the minerals lanthanite- (La), [ 3 ][ 4 ] lanthanite- (Ce), [ 5 ] and lanthanite- (Nd). [ 6 ] This mineral group has the general chemical formula of (REE) 2 (CO 3) 3 ·8 (H 2 O). Lanthanites include La, Ce, and Nd as major elements and ...