| Minute crystals of brookite have been detected with anatase and rutile in the iron-ore of Cleveland in Yorkshire. |
| Titanium dioxide has three crystalline forms including anatase, rutile and brookite. |
| Titanic acid occurs in nature crystallized in anatase, arkansite, brookite, and rutile. |
| Brookite occurs only as crystals, never in compact masses, and is usually associated with either anatase or rutile. |
| The area is probably producing the most brookite from a quartz-crystal deposit at present, though it is hard to find any good ones for sale. |
| Brookite is best known from alpine-cleft-type occurrences, where it is round with anatase, rutile, titanite, quartz, adularia, albite, hematite, calcite, and chlorite. |
