Anatase Titanium Dioxide features
Composed of titanium dioxide, one of the three kinds of mineral species, two other is rutile titanium ore and plate. Anatase of physical properties, production condition and USES and rutile, and itself can also become rutile.
It originated in igneous and metamorphic rocks in vein, usually appearing in placer deposit, a hard, shiny tetragonal crystal, and has a different color. Famous nervation ore deposits are found in many parts of the Alps. Many anatase is formed by sphene weathering, erosion and it itself can become rutile. By the formation of anatase rutile homogeneous illusion (i.e., replacement products with the same shape) in Brazil and ural mountain detrital deposit is very common. Class quality with like alternative Fe, Sn, Nb, Ta, etc. In addition, it is found that the content of rare earth elements and Y family U, Th.
Structure and morphology
Tetragonal crystal system, a0 = 0.379 nm, c0 = 0.951 nm; Z = 4. Under the 915 ℃ to rutile. Compound double cone, D4h - 4 / MMM (L44L25PC). General cone shaped crystal shape, slab, column. Main simplex: parallel double c, four square column m, a, square double cone p, n, q, v, e, etc.
Brown, yellow, shallow green, blue, shallow purple, colored, accidentally see almost colorless. Striation colorless to pale yellow. King kong luster. Cleaves completely. Hardness is 5.5 to 6.5. Relative density 3.82 to 3.97.
Under polarizer, brown, yellow, blue, green, orange, yellow, blue, light green color. One axis crystal (-). Small dark varieties have time sexual abnormality, 2 v, No = 2.561 2.562, Ne = 2.488 to 2.489.
Occurrence and combination
Anatase is unstable, so than rutile rare. Forming conditions are similar to rutile. As accessory mineral s in crystalline rock, or as titanite, ilmenite, titanium magnetite alteration of the product. Anatase of other physical properties, production conditions, and USES and rutile are similar, but not as stable rutile and common.