Brockite
Formula: (Ca,Th,Ce)PO4·H2OMohs scale hardness: 3-4Specific gravity: 3,7-4,1 g/cm3Rare earth elements: CeRare earth content, %: Ce2O3 7,4; ThO2 35,9Other constituents, %: As, VMineralklasse: Phosphate, Arsenate, VanadateMineral Group: Rhabdophane group.
Brockite is a rare earth phosphate mineral. It is radioactive due to the thorium content. Brockite occurs in granite and granite pegmatite as an accessory mineral. Associated minerals include monazite, bastnasite, xenotime, thorite, zircon, apatite, rutile and hematite.
Distribution: In the USA, in a prospect pit about 1 km east of the Bassick mine, Querida, Wet Mountains, and at the Hardwick mine and Nightingale shaft, Custer Co., Colorado; in the Bear Lodge Mountains, Crook Co., Wyoming; from the Diamond Creek district, Lemhi Co., Idaho and the Lemhi Pass district, Idaho-Montana; found in Monroe Canyon, Sevier Co., Utah; from the Laughlin Peak area, Colfax Co., New Mexico; in the Rawhide Mountains, Mohave Co., Arizona.
At Mont Saint-Hilaire, Quebec, Canada. From Kizilcaoren, Turkey. In Japan, from Atagoyama,
Shionhira, Shin-yashikiike, and Ishizuka, Ishikawa district, Fukushima Prefecture, Japan.
References
https://en.wikipedia.org
http://www.mindat.org/min-780.html
http://www.handbookofmineralogy.org/pdfs/brockite.pdf
http://www.minsocam.org/ammin/AM47/AM47_1346.pdf
https://en.wikipedia.org/wiki/Brockite
http://webmineral.com/data/Brockite.shtml#.V55xKRI4B0s
http://www.handbookofmineralogy.org/pdfs/brockite.pdf