12 miles east is on the Eau Claire river....next town is Birnamwood....Cannot find any Reef Family in Marathon County....Closest name Reef is in Aniwa.....
Marathon County
County Route U road cut. This road cut in the border zone of the Stettin Pluton on County Route U east of the Little Rib River, west of Wausau (SW 1/4 sec. 18 T.29N. R.7E.) exposes nepheline syenite pegmatites, syenite, and syenitized country rock: apatite, biotite, cancrinite, epidote, fayalite, monazite, nepheline (pinkish grains 1-2 cm across), riebeckite, plagioclase, potassium feldspar, sodic pyroxene (Myers et al. 1984).
County Z quarries. Hornblende granite of the Wolf River batholith with locally pegmatitic phases is exposed in several quarries near Hatley (SE 1/4 sec. 18 and NE 1/4 sec. 19 T.29N. R.10E.): hornblende, potassium feldspar, quartz (Institute on Lake Superior Geology 1973).
Eason exploration. This 200-foot-deep abandoned mine shaft was sunk in mineralized chloritic schist near Eason (sec. 26 T.29N. R.9E.): chalcopyrite, chlorite, gold, malachite, pyrite, quartz, sphalerite (LaBerge and Myers 1983).
Employers Mutual outcrops. Outcrops of quartz syenite are abundant around the parking lot of Employers Mutual Insurance buildings on the west edge of Wausau (NW 1/4 SE 1/4 sec. 27 T.29N. R.7E.): fluorite, magnetite, potassium feldspar, sodic pyroxene, quartz (LaBerge and Myers 1983).
Fluorite quarry. This quarry exposes granitic rocks cut by pegmatites north of Wausau (NE sec. 6 T.29N. R.7E.): fluorapatite, fluorite, potassium feldspar, quartz (L. Brown, pers. com.).
Hamburg schist. Schist crops out along the Rib River west of Hamburg (sec. 14 T.30N. R.4E.): almandine, biotite, cordierite, quartz, staurolite (Weidman 1907b).
Little Chicago "nephrite" Outcrops of metamorphosed volcanic rocks occur along the Little Rib River near Little Chicago. Some material, a compact massive actinolite, was briefly marketed as jade: actinolite, calcite, chlorite, diopside, epidote, plagioclase, serpentine (Wisconsin Geological and Natural History Survey files; L. Brown, pers. com.).
Moonstone quarry. This abandoned quarry exposes pyroxene syenite near Stettin (SE 1/4 sec. 14 T.29N. R.6E.): aegirine-augite, arfvedsonite, anorthoclase (grains up to 35 cm long showing moonstone schiller), biotite, nepheline, riebeckite (LaBerge and Myers 1983; Myers et al. 1984; L. Brown, pets. com.).
Mosinee Hill quarry. This quarry west of Wausau (NW 1/4 sec. 26 T.26N. R.7E.) exposes a large quartzite roof pendant in granitic rocks of the Nine-Mile pluton: anatase, brookite, quartz (L. Brown, pers. com.).
Reef property. This hydrothermal deposit, known solely from drill core, occurs 12 miles east of Wausau: chalcopyrite, gold (visible grains to nuggets up to 1 cm across), pyrrhotite, quartz (Anonymous 1991; La Berge, pers. com.).
"Rotten granite" quarries. Many large quarries are dug in weathered granitic grus of the Wausau complex plutons such as in T.27N. R.6E (e.g., secs. 6, 7, and 12); T.28N. R.6E. (e.g., secs. 31, 32, 33, and 34); T.27N. R.5E. (e.g., secs. 1 and 12); and T.28N. R.7E (e.g., secs. 19 and 20). One of the best is the Wimmer No. 3 pit. The granites are pegmatitic and have many miarolitic cavities: aegirine, allanite, almandine, anatase, andradite, anhydrite, anorthoclase, arsenopyrite, barite, bavenite, bertrandite, beryl, biotite, boulangerite, brookite, calaverite, calcite, catapleiite, chalcopyrite, cheralite (bipyramidal microcrystals), chlorite, columbite-tantalite, cookeite, elbaite, eudialyte, fayalite, fluorapatite, fluorite, galena, goethite, gold, grossular, hastingsite, hematite, hisingerite, ilmenite, jamesonite, kaolin, lepidochrocite, magnetite, microlite, monazite, muscovite, natrolite, opal (fluorescent), parisite-synchisite (brownish microcrystals), phenakite (clear transparent crystals, rarely up to 1 inch long), pyrite, plagioclase, potassium feldspar (some "amazonite"), quartz (some large smoky crystals), romanechite, futile, sanidine, schorl, siderite, smectite, sphalerite, stilpnomelane, thorogummite, titanite, xenotime, zinnwaldite, zircon (Falster 1977, 1981, 1984a, 1985, 1986a, 1987; Falster and Simmons 1989; T. Buchholz, pers. com.).
Rozellville serpentine. Outcrops of serpentinite occur south of Rozellville (secs. 15, 16, and 22 T.26N. R4E.): chlorite, olivine, serpentine, talc (LaBerge and Myers 1983).
Stettin aegirine. Outcrops of aegirine-bearing syenite occur near Stettin in E 1/2 sec. 21 T.29N. R.6E.: aegirine, potassium feldspar (L. Brown, pers. com.).
Stettin nepheline syenite. Outcrops of gneissic nepheline syenite occur in NE 1/4 sec. 27 T.29N. R.6E. near Stettin: aegirine, nepheline, potassium feldspar, zircon (Geisse 1951; Vickers 1956; Stobbe and Murray 1956).
Stettin pegmatite. Syenitic pegmatite crops out near Stettin (NW 1/4 sec. 22 T.29N. R.6E.): aegirine, crocidolite, fluorite, "lithium mica," nepheline, plagioclase, potassium feldspar, pyrochlore, riebeckite, futile, zircon (Weidmann 1907a).
Thorium mine. Overgrown tailings piles of old thorium mine and adjacent outcrops expose syenitic rocks of the Stettin pluton: aegirine, apatite, goethite, ilmenite, magnetite, potassium feldspar, pyrochlore (yellow octahedra in vugs and in aegirine), thorite (red to orange prisms), zircon (T. Buchholz, pers. com.).
Zircon quarry. Syenite with nepheline syenite dikes is exposed in small quarry in SE1/4 SE sec. 22 T.29N. R.6E. near Stettin: aegirine, fluorite, nepheline, plagioclase, potassium feldspar, zircon (Stobbe and Murray 1956).
Zunker's pit. This small quarry is in syenite in the SW 1/4 SE 1/4 sec. 22 T.29N. R.6E. near Stettin: aegirine, fluorite, potassium feldspar, zircon (abundant brown euhedral crystals).