Edward S. Grew  Research Professor of Geological Sciences  Ph.D. Harvard University, 1971  Phone: (207)581-2169  Fax: (207)581-2202

Research

My current research focuses on the minerals of boron and beryllium and the role of these two elements in the changes rocks undergo at high temperatures and pressures in the earth's crust, especially in the granulite facies. More recently, I have developed an interest in phosphate minerals, having discovered three new species in the Larsemann Hills, Prydz Bay , Antarctica . Following the tradition of the late Charles Guidotti, formerly a professor in our department, I describe my research as “petrologic mineralogy” because I study minerals in their petrologic context. Work with light elements requires special techniques so an integral component of my research is analysis for Li, Be and B in minerals with the ion microprobe (secondary ion mass spectrometry). I do these analyses in collaboration with Charles Shearer at the University of New Mexico in Albuquerque . My current research activity includes:

• Beryllium minerals in sapphirine-quartz granulites and anatectic pods of the ultrahigh-temperature granulite-facies Archean Napier Complex of Enderby Land, Antarctica, based on fieldwork carried out on the 40th Japanese Antarctic Research Expedition (November, 1998-March, 1999) and on two Australian Antarctic Research Expeditions between 1977 and 1980.With up to 2700 parts per million weight beryllium, sapphirine is the main carrier of this element in the granulites, whereas the pods contain a variety of beryllium minerals: the new species khmaralite related to sapphirine, the oxide “musgravite” (technically now magnesiotaaffeite-6N’3S), and the silicate surinamite, which formed from breakdown of sapphirine – khmaralite solid solutions (photographs).
• Borosilicate minerals in granulite-facies rocks. My current National Science Foundation supported project is a study of boron-rich paragneisses in the Larsemann Hills based on samples collected on the Australian National Antarctic Research Expedition in 2003-2004 with Chris Carson (Geosciences Australia). The ferromagnesian borosilicates grandidierite and prismatine are major rock-forming minerals in these paragneisses (photograph). Geochemical data on over 50 samples suggests affinities with Broken Hill , Australia , a famous ore deposit. The Larsemann Hills is the type locality for boralsilite, a mineral related to sillimanite I discovered in 1998, which Chris and I found at several localities during the 2003-2004 season (photograph).
• Phosphate minerals in granulite-facies metamorphic rocks and and anatectic pods. The Larsemann Hills contains a remarkable variety of phosphate minerals for a metamorphic complex (9 species so far), including 3 of the 4 known polytypes of iron magnesium fluorphosphate wagnerite and 3 new species.

Click for more information  on related work at the  University of Maine's  Crustal Studies Group   (Fig. 4) A specimen of pegmatite I collected in January, 1999 from the Napier Complex, Antarctica (Scale in units of 2.5 cm). Sapphirine-khmaralite (Spr) is separated from quartz (Qz, gray) by a corona of garnet (pink, Grt) and sillimanite in the center of the specimen (from Grew et al., 2000).
(Fig. 7) Photomicrographs in plane light of the pegmatite specimen illustrated above. Scale applies to both photographs. (a) Part of corona around deeply embayed sapphirine-khmaralite (Spr) showing inner sillimanite (Sil) zone and part of outer garnet (Grt) zone with surinamite (Sur). (b) Ilmenite-hematite intergrowth (opaque) with tabular musgravite (Mgr), minor surinamite (Sur) and relict sapphirine-khmaralite (Spr) (from Grew et al., 2000).
Photomicrograph of prismatine (high relief, pale) around grandidierite (blue) in plagioclase. Brown grains are tourmaline. Plain light. Larsemann Hills.
Photomicrograph of twinned boralsilite prisms. Crossed nicols. Larsemann Hills.

Selected Recent References

Grew, E.S. and Anovitz, L. M. (eds) (1996) Boron: Mineralogy, Petrology, and Geochemistry. Reviews in Mineralogy, v. 33, Mineralogical Society of America (updated and reprinted in 2002).

Grew, E.S., McGee, J.J., Yates, M. G., Peacor, D.R., Rouse, R.C, Huijsmans, J.P.P., Shearer, C.K., Wiedenbeck, M., Thost, D. E., and Su, S.-C. (1998) Boralsilite (Al₁₆B₆Si₂O₃₇): A new mineral related to sillimanite from pegmatites in granulite-facies rocks. Am. Mineral., 83, 638-651.

Grew, E.S., Pertsev, N.N., Vrána, S., Yates, M. G., Shearer, C.K. and Wiedenbeck, M. (1998) Kornerupine parageneses in whiteschists and other magnesian rocks: is kornerupine + talc a high-pressure assemblage equivalent to tourmaline + orthoamphibole? Contrib. Mineral. Petrol., 131, 22-38.

Grew, E.S., Yates, M. G., Huijsmans, J.P.P., McGee, J.J., Shearer, C.K., Wiedenbeck, M., and Rouse, R.C. (1998) Werdingite, a borosilicate new to granitic pegmatites. Canad. Mineral., 36, 399-414.

Grew, E.S., Yates, M.G., Adams , P., Kirkby, R., and Wiedenbeck, M. (1999) Harkerite from the Crestmore Quarry,  Riverside County , California and Cascade Slide, Adirondack Mountains , New York : A contrast in metamorphic pressure. Can. Mineral., 37, 277-296.

Barbier, J, Grew, E.S., Moore, P.B., Su, S.-C. (1999) Khmaralite, a new beryllium-bearing mineral related to sapphirine: A superstructure resulting from partial ordering of Be, Al and Si on tetrahedral sites. Am. Mineral., 84, 1650-1660

Grew, E.S., Yates, M.G., Shearer, C.K., Hagerty, J.J., Sheraton, J.W., and Sandiford, M. (2006) Beryllium and other trace elements in paragneisses and anatectic veins of the ultrahigh-temperature Napier Complex, Enderby Land, East Antarctica: The role of sapphirine. Journal of Petrology, 47, 859-882

Asami, A., Suzuki, K. and Grew, E.S. (2002) Chemical Th-U-total Pb dating by electron microprobe analysis of monazite, xenotime and zircon from the Archean Napier Complex, East Antarctica : Evidence for ultra-high-temperature metamorphism at 2400Ma. Precambrian Research, 114, 249-275

Barbier, J., Grew, E.S., Hålenius, E.,Hålenius, U. and Yates, M.G. (2002) The role of Fe and cation order in the crystal chemistry of surinamite, (Mg,Fe²⁺)₃(Al,Fe³⁺)₃O[AlBeSi₃O₁₅]: A crystal structure, Mössbauer spectroscopic, and optical spectroscopic study. Am. Mineral., 87, 501-513

Christy, A.G., Tabira, Y., Hölscher, A., Grew, E. S., and Schreyer, W. (2002) Synthesis of beryllian sapphirine in the system MgO-BeO-Al₂O₃-SiO₂-H₂O and comparison with naturally occurring beryllian sapphirine and khmaralite. Part 1: Experiments, TEM and XRD. American Mineralogist, v. 87, p. 1104-1112.