Brookita
Sign in to saveBrookite is the orthorhombic variant of titanium dioxide (TiO2), which occurs in four known natural polymorphic forms (minerals with the same composition but different structure). The other three of these forms are akaogiite (monoclinic), anatase (tetragonal) and rutile (tetragonal). Brookite is rare compared to anatase and rutile and, like these forms, it exhibits photocatalytic activity. Brookite also has a larger cell volume than either anatase or rutile, with 8 TiO2 groups per unit cell, compared with 4 for anatase and 2 for rutile. Iron (Fe), tantalum (Ta) and niobium (Nb) are common impu
Key facts
- Mineral.name
- Brookite
- Mineral.image
- Brookite-gem7-07a.jpg
- Mineral.imagesize
- 260px
- Mineral.caption
- Brookite from Balochistan
- Mineral.category
- Oxide minerals
- Mineral.formula
- TiO2
- Mineral.molweight
- 79.88 g/mol
- Mineral.strunz
- 4.DD.10 (10 ed) 4/D.15-10 (8 ed)
- Mineral.dana
- 4.4.5.1
- Mineral.system
- Orthorhombic
- Mineral.class
- Dipyramidal (mmm) H-M symbol: (2/m 2/m 2/m)
- Mineral.symmetry
- Pbca
- Mineral.unit cell
- a = 5.4558 Å, b = 9.1819 Å, c = 5.1429 Å; Z = 8
- Mineral.color
- Deep red, reddish brown, yellowish brown, brown, or black
- Mineral.habit
- Tabular and striated, pyramidal or pseudohexagonal
- Mineral.twinning
- On {120}, uncertain
- Mineral.cleavage
- Poor on {120}, in traces on {001}
- Mineral.fracture
- Subconchoidal to irregular
via Wikipedia infobox
Wikidata facts
- Subclass of
- oxide class of minerals
- Has part
- titanium dioxide
- Named after
- Henry-James Brooke
- Image
- Brookit2 Pakistan.jpg
Show 8 more facts
- Nickel-Strunz '10th ed', review of (9th ed/ 2009 update)
- 4.DD.10
- Commons category
- Brookite
- chemical formula
- TiO₂
- Nickel-Strunz 9th edition (updated 2009)
- 4.DD.10
- crystal system
- orthorhombic crystal system
- described by source
- Encyclopædia Britannica 11th edition
- IMA Mineral Symbol
- Brk
- Strunz 8th edition (series ID, updated)
- IV/D.07
Sources (2)
via Wikidata · CC0
Article · Español
La brookita es un mineral con fórmula química TiO2. Pertenece al grupo de los óxidos, cristaliza en sistema ortorrómbico, tiene una dureza de 5,5-6 en la escala de Mohs, fractura , exfoliación débil, brillo adamantino y raya blanca, gris, o amarillenta. Se trata de una de las tres formas minerales del dióxido de titanio, junto con la anatasa y el rutilo. La belleza de algunos de los cristales de este mineral, especialmente los que pertenecen a la variedad , ha hecho de él un objeto muy valorado por los coleccionistas.
Abstract from DBpedia / Wikipedia · CC BY-SA