Formula: (Ce,La,Nd,Th)PO4 Monoclinic
Description: Monazite refers to a group of minerals dominated by various rare earth elements. These minerals commonly form reddish brown to yellowish tabular crystals and granular masses in granitic rocks and placer deposits derived from them.
FLORENCE COUNTY: Monazite is an accessory mineral in the Hoskins Lake Granite exposed at numerous sites in the county. Some outcrops bearing monazite are in a railroad cut in SW SE sec. 7 T.38N. R.20E. and in SE SE sec. 28 T.38N. R.19E. (Sims et al., 1992).
IRON COUNTY: Monazite occurs as an accessory in the kyanite-bearing gneisses and schists in the Powell area, in Sec. 28, 29, 32, 33 T.42N R.4E. It can be found in a roadcut on Hwy. 182 west of Powell at SE SE Sec. 28 (Holm et al., 1998).
MARATHON COUNTY: Monazite occurs as an accessory in the nepheline syenite pegmatites of the Stettin pluton, such as is exposed along County U 1 km. east of the Little rib River, SW SW sec. 18 T.29N. R.7E. (Myers et al., 1984).
— Monazite is rarely found as grains up to 1 mm. across in pegmatites of the Ninemile Pluton, as exposed in pits south of Rib Mountain (Falster, 1987, Myers et. al., 1984; Buchholz, Falster and Simmons, 1999). Monazite is recorded as occurring at the Koss Pit (SW sec. 2 T27N R.5E), the the Ladick Quarry (sec. 19 and 20 T. 27N. R.6E.) and the Wimmer #3 pit (NW sec. 19 T.28N R7E) (Buchholz and Simons, 2002).
— Yellow to orange monazite-(Ce) crystals up to 4.5 mm are found at the Maguire Pit, just west of the LaDick “rotten granite” quarries, west of Wausau. (Buchholz et. al., 2004). Both monazite-(Ce) and monazite-(Nd) are verified from these dikes (Falster, Buchholz and Simmons, 2012)
MARINETTE COUNTY: Monazite is an accessory mineral in the Hoskins Lake Granite exposed at numerous sites in the county. Banks and Cain (1969) report monazite in this rock exposed in roadcuts on the west side of U.S. Hwy. 141, in the center of sec. 1 T.37N. R.20E., southeast of Niagara. Prinz (1965) describes monazite in this rock from outcrops in S 1/2 sec. 12 and N 1/2 sec. 13 T.38N. R.19E. and in NE sec. 17 T.38N. R.20E.
— Monazite occurs with K feldspar, garnet and muscovite in aplite dikes in NE SE sec. and NW NE sec. 15 T.37N. R.18E. (Sims et al., 1992).
PRICE COUNTY: Monazite occurs as an accessory in sillimanite schist in drill core taken from near Park Falls. (Holm et al., 2001.)
WOOD COUNTY: Monazite occurs as crystals on iron-free sphalerite at the Vesper quarry, SW NE sec. 32 T.24N. R.4E. (Buchholz, pers. comm.)
— Monazite-Ce is an accessory in the granite exposed in the Haske quarry in Sec. 25 T.24N. R.2E (Buchholz, et al., 2005a).