Dimorphous with Polycrase (_q.v._), and of same composition. Orthorhombic; isomorphous with priorite (_q.v._). G = 4·5-5·0; H = 6¹⁄₂. Bright black; translucent. Hitterö and Arendal, Norway. Blomstrandite. Hydrated titano-columbate of U, with some Fe and Ca. TiO₂ = 10·7%. Massive. G = 4·17-4·25. H = 5¹⁄₂. Black; opaque. Nohl, Sweden. _Bodenite._ A variety of Allanite (_q.v._), rich in Al and Ca, with no Be. Yttr = 17; Cer = 18%. Monoclinic. As Allanite. Boden, near Marienburg. _Britholite._ A basic phosphosilicate of cerium metals, with Fe, Ca, Mg, Na, F. Cer = 60·5-60·9%. Hexagonal; habit prismatic. G = 4·446. H = 5¹⁄₂. Brown; transparent. Naujakasik, Greenland. _Bröggerite._ A variety of Uraninite (_q.v._), with rare earths, Th, Pb, Fe, Ca, Si, aq., etc. Cer = 0·4; Yttr = 1·4-4·3; ThO₂ = 4·7-6·1%. Traces of ZrO₂. Cubic, in octahedra and dodecahedra. G = 8·7-9·0. H = 5-6. Black; translucent to opaque. Anneröd, near Moos, Norway. ~Brookite.~ Titanium dioxide, TiO₂ = 99-100%; trimorphous with Anatase and Rutile. Orthorhombic. G = 3·87-4·01. H = 5¹⁄₂-6. Brown; opaque. Dauphiné; Urals; Switzerland; Magnet Cove, Arkansas. _Calciothorite._ A variety of Thorite containing lime--5ThSiO₄,2Ca₂SiO₄ + 10H₂O. ThO₂ = 59·3%. Completely amorphous. G = 4·114. H = 4¹⁄₂. Deep red; translucent. Islands of Läven and Arö, Langesund Fiord, Norway. _Cappelenite._ A borosilicate of rare earth metals and barium, with traces of Th, Ca, K, Na, aq. Approximately BaSiO₃, YBO₃. Cer = 4·2; Yttr = 52·5%. Hexagonal; habit prismatic. G = 4·407. H = 6-6¹⁄₂. Greenish brown; translucent. Island of Klein-Arö, Langesund Fiord, Norway. _Caryocerite_ (Karyocerite). Complex fluosilicate of E, with Ta, Th, Ca; also CO₂, P₂O₅, B, Al, Fe, Mn, U, Mg, Na, aq., etc. Approaching Melanocerite, (_q.v._), but richer in Th. Very complex. Cer = 41·8; Yttr = 2·2; ThO₂ = 13·6; ZrO₂ = 0·5%. Rhombohedral, but isotropic; apparently a pseudomorph after Melanocerite (_q.v._) G = 4·295. H = 5-6. Nut brown; translucent. Faces very brilliant, but striated. Lustre vitreous to resinous. Various rocks and shoals round Arö Island, Langesund Fiord, Norway. _Castelnaudite._ A variety of Xenotime (_q.v._) containing Zr. Yttr = 60·4; ZrO₂ = 7·4%. Tetragonal. G = 4·5. H = 4-5. Greyish white to pale yellow. Diamond sands of Brazil. _Cataplejite_ (Kataplejite). H₄(Na₂,Ca)ZrSi₃O₁₁. ZrO₂ = 29·6-40% (usually 30-33%). Monoclinic, pseudohexagonal. Becomes truly hexagonal at 140°C. G = 2·8. H = 6. Yellow to brown; transparent to opaque. A blue variety is known which contains no calcium. Islands of Langesund Fiord, Norway; Narsarsuk, Greenland. ~Cerite.~ A basic silicate of Cerium metals, with Ca and Fe. Approximately H₃(Ca,Fe)Ce₃Si₃O₁₃. Cer = 50·7-71·8%. In a variety from Batoum, Tschermak reports Yttr = 7·6 and ZrO₂ = 11·7%.