Skip to main content Accessibility help

Beusite-(Ca), ideally CaMn22+(PO4)2, a new graftonite-group mineral from the Yellowknife pegmatite field, Northwest Territories, Canada: Description and crystal structure

  • Frank C. Hawthorne (a1), Michael A. Wise (a2), Petr Černý (a1), Yassir A. Abdu (a3), Neil A. Ball (a1), Adam Pieczka (a4) and Adam Włodek (a4)...


Beusite-(Ca), ideally Ca ${\rm Mn}_{\rm 2}^{2 +} $ (PO4)2, is a new graftonite-group mineral from the Yellowknife pegmatite field, Northwest Territories, Canada. It occurs in a beryl–columbite–phosphate rare-element pegmatite where it is commonly intergrown with triphylite–lithiophilite or sarcopside, and may form by exsolution from a high-temperature (Li,Ca)-rich graftonite-like parent phase. It occurs as pale-brown lamellae 0.1–1.5 mm wide in triphylite, and is pale brown with a vitreous lustre and a very pale-brown streak. It is brittle, has a Mohs hardness of 5, and the calculated density is 3.610 g/cm3. Beusite-(Ca) is colourless in plane-polarized light, and is biaxial (+) with α = 1.685(2), β = 1.688(2), γ = 1.700(5), and the optic axial angle is 46.0(5)°. It is non-pleochroic with X || b; Y ˄ a = 40.3° in β obtuse; Z ˄ a = 49.7° in β acute. Beusite-(Ca) is monoclinic, has space group P21/c, a = 8.799(2), b = 11.724(2), c = 6.170(1) Å, β = 99.23(3)°, V = 628.3(1) Å3 and Z = 4. Chemical analysis by electron microprobe gave P2O5 41.63, FeO 19.43, MnO 23.63, CaO 15.45, sum 100.14 wt.%. The empirical formula was normalized on the basis of 8 anions pfu: (Ca0.94Fe0.92Mn1.13)Σ2.99(PO4)2.00. The crystal structure was refined to an R1 index of 1.55%. Beusite-(Ca) is a member of the graftonite group with Ca completely ordered at the [8]-coordinated M(1) site.


Corresponding author


Hide All

Associate Editor: Anthony Kampf



Hide All
Bartelmehs, K.L., Bloss, F.D., Downs, R.T. and Birch, J.B. (1992) Excalibr II. Zeitschrift für Kristallographie, 199, 186196.
Beus, A.A. (1950) Magniophilite and mangankoninckite, two new minerals from pegmatites. Doklady Akademii Nauk SSSR, 73, 12671279.
Bild, R.W. (1974) New occurrences of phosphates in iron meteorites. Contributions to Mineralogy and Petrology, 45, 9198.
Calvo, C. (1968) The crystal structure of graftonite. American Mineralogist, 53, 742750.
Černý, P. (1989) Exploration strategy and methods for pegmatite deposits of tantalum. Pp. 274302 in: Lanthanides, Tantalum and Niobium (Möller, P., Černý, P. and Saupe, F., editors). Springer-Verlag, New York.
Černy, P., Selway, J.B., Ercit, T.S., Breaks, F.W., Anderson, A.J. and Anderson, S.D. (1998) Graftonite-beusite in granitic pegmatites of the Superior Province: A study in contrasts. The Canadian Mineralogist, 36, 367376.
Ercit, T.S., Tait, K., Cooper, M.A., Abdu, Y., Ball, N.A., Anderson, A.J., Černý, P., Hawthorne, F.C. and Galliski, M. (2010) Manitobaite, Na16Al8(PO4)30, a new phosphate mineral from Cross Lake, Manitoba, Canada. The Canadian Mineralogist, 48, 14551463.
Fransolet, A.-M., Keller, P. and Fontan, F. (1986) The phosphate mineral associations of the Tsaobismund pegmatite, Namibia. Contributions to Mineralogy and Petrology, 92, 502517.
Gagné, O. and Hawthorne, F.C. (2015) Comprehensive derivation of bond-valence parameters for ion pairs involving oxygen. Acta Crystallographica, B71, 562578.
Galliski, M.A., Oyarzábal, J.C., Márquez-Zavalía, M.F. and Chapman, R. (2009) The association qingheiite-beusite-lithiophilite in the Santa Ana pegmatite, San Luis, Argentina. The Canadian Mineralogist, 47, 12131223.
Guastoni, A., Nestola, F., Mazzoleni, G. and Vignola, P. (2007) Mn-rich graftonite, ferrisicklerite, staněkite and Mn-rich vivianite in a granitic pegmatite at Soè Valley, central Alps, Italy. Mineralogical Magazine, 71, 579585.
Hålenius, U.F., Hatert, F.M., Pasero, M. and Mills, S.J. (2017) CNMNC Newsletter No. 36, April 2017, Mineralogical Magazine, 81, 403409.
Hawthorne, F.C. (1983) Quantitative characterization of site-occupancies in minerals. American Mineralogist, 68, 287306.
Hawthorne, F.C. (1998) Structure and chemistry of phosphate minerals. Mineralogical Magazine, 62, 141164.
Hawthorne, F.C. and Pieczka, A. (2018) Classification of the minerals of the graftonite group. Mineralogical Magazine, 82, 13011306.
Hawthorne, F.C., Ungaretti, L. and Oberti, R. (1995) Site populations in minerals: terminology and presentation of results of crystal-structure refinement. The Canadian Mineralogist, 33, 907911.
Huminicki, D.M.C. and Hawthorne, F.C. (2002) The crystal chemistry of phosphate minerals. Pp. 123253 in: Phosphates – Geochemical, Geobiological and Materials Importance (Kohn, M.L., Rakovan, J. and Hughes, J. M., editors). Reviews in Mineralogy & Geochemistry, 48. Mineralogical Society of America and the Geochemical Society, Washington, DC.
Hurlbut, C.S. Jr. and Aristarain, L.F. (1968) Beusite, a new mineral from Argentina, and the graftonite–beusite series. American Mineralogist, 53, 17991814.
Nord, A.G. and Ericsson, T. (1982) The cation distribution in synthetic (Fe,Mn)3(PO4)2 graftonite-type solid solutions. American Mineralogist, 67, 826832.
Olsen, E.J., Kracher, A., Davis, A.M., Steele, I.M., Hutcheon, I.D. and Bunch, T.E. (1999) The phosphates of IIIAB iron meteorites. Meteorics and Planetary Science, 34, 285300.
Penfield, S.L. (1900) On graftonite, a new mineral from Grafton, New Hampshire and its intergrowth with triphylite. American Journal of Science, 159, 2032.
Pieczka, A. (2007) Beusite and an unusual Mn-rich apatite from the Szklary granitic pegmatite, Lower Silesia, southwestern Poland. The Canadian Mineralogist, 45, 901914.
Pouchou, J.L. and Pichoir, F. (1985) ‘PAP’ (φρZ) procedure for improved quantitative microanalysis. Pp. 104106 in: Microbeam Analysis (Armstrong, J.T., editor). San Francisco Press, San Francisco, California, USA.
Rancourt, D.G. and Ping, J.Y. (1991) Voigt-based methods for arbitrary-shape static hyperfine parameter distributions in Mössbauer spectroscopy. Nuclear Instruments and Methods in Physics Research, B58, 8597.
Sheldrick, G.M. (2008) A short history of SHELX. Acta Crystallographica, A64, 112122.
Smeds, S.A., Uher, P., Černý, P., Wise, M.A., Gustafsson, L. and Penner, P. (1998) Graftonite – beusite in Sweden: primary phases, products of exsolution, and distribution in zoned populations of granitic pegmatites. The Canadian Mineralogist, 36, 377394.
Stalder, M. and Rozendaal, A. (2002) Graftonite in phosphatic iron formations associated with the mid-Proterozoic Gamsberg Zn-Pb deposit, Namaqua Province, South Africa. Mineralogical Magazine, 66, 915927.
Steele, I.M., Olsen, E., Pluth, J. and Davis, A.M. (1991) Occurrence and crystal structure of Ca-free beusite in the El Sampal IIIA iron meteorite. American Mineralogist, 76, 19851989.
Tait, K.T., Hawthorne, F.C. and Wise, M.A. (2013) The crystal structure of the graftonite–beusite minerals. The Canadian Mineralogist, 51, 653662.
Vignola, P., Diella, V., Oppizzi, P., Tiepolo, M. and Weiss, S. (2008) Phosphate assemblages from the Brissago granitic pegmatite, western southern Alps, Switzerland. The Canadian Mineralogist, 46, 635650.
Wise, M.A. and Černý, P. (1990) Beusite-triphylite intergrowths from the Yellowknife pegmatite field, Northwest Territories. The Canadian Mineralogist, 28, 133139.
Wise, M.A., Hawthorne, F.C. and Černý, P. (1990) Crystal structure of a Ca-rich beusite from the Yellowknife pegmatite field, North West Territories. The Canadian Mineralogist, 28, 141146.


Type Description Title
Supplementary materials

Hawthorne et al. supplementary material
Hawthorne et al. supplementary material 1

 Unknown (244 KB)
244 KB


Full text views

Total number of HTML views: 0
Total number of PDF views: 0 *
Loading metrics...

Abstract views

Total abstract views: 0 *
Loading metrics...

* Views captured on Cambridge Core between <date>. This data will be updated every 24 hours.

Usage data cannot currently be displayed