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PLATE 1.-FIG. 1.-Aravalli schist country, south-west of Kundanpur, Jhabua


FIG. 2.-View of Aravalli quartzite country, N.E. of Virpur, Balasinor


PLATE 2.-FIG. 1.-Deccan trap country, Samoi, Jhabua.

FIG. 2.-General view of Aravalli quartzite ridges, Umria, Bariya


PLATE 3.-FIG. 1.--Aravalli quartzite (dip-slope), Hadaph river-section, Umria,
Bariya State.

FIG. 2.-Low-dipping Aravalli slaty and quartzitic bands, south of
Mekhar, Godhra.

PLATE 4.--FIG. 1.—Much jointed Aravalli quartzite, Edalwara, Bariya State.
FIG. 2.-Weathering of granite, Kothamba, Lunavada State.

PLATE 5.-Geological map of Gujarat and Southern Rajputana.

PLATE 6.-FIG. 1.-Cassiterite (C) interstitial to wolfram (W). Quartz (Q). P. S. 252. X 54.

FIG. 2.-Cassiteritic (C) and molybdenite (M) interstitial to wolfram (W). Bakelite (B). P. S. 251. Crossed nicols. X 54.

FIG. 3.--Wolfram (W) partly enclosing a tourmaline crystal (T) in quartz (Q). P. S. 243. x 54.

FIG. 4.-Scheelite (dark grey), replacing wolfram (light grey). P. S. 231. X. 54.

PLATE 7.—FIG. 1.-Wolfram (W) crystal replaced by scheelite (S). Cassiterite (C) and quartz (Q). Bakelite (B). P. S. 251. X 28.

FIG. 2.-Quartz (Q) replacing wolfram (W). A little pyrite (P).

P. S. 236. × 54.

FIG. 3.-Pyrite (white) veinlets in quartz (Q) and wolfram (W). P. S.

232 × 54.

FIG. 4.-Pyrite (P) veining tourmaline (T), and both replaced and veined by chlorite (C). P. S. 239 B. X 54.

PLATE 8.-FIG. 1.--Pyrite (P) and chalcopyrite (C), veining arsenopyrite (A). Quartz (Q). P. S. 164. X 28.

FIG. 2.-Arsenopyrite (white) veined by chalcopyrite (grey) and carbonate (black). P. S. 164. X 180.

FIG. 3.-Arsenopyrite needles in chlorite (dark grey); the latter replaces quartz (lighter grey) and galena (white). Pyrite (P). P. S. 236.

X 54.

FIG. 4.--Sphalerite (S) veining and replacing arsenopyrite (A). Also chalcopyrite (C) and carbonate (Ca). P. S. 242.

X 84.

PLATE 9. FIG. 1.-Quartz veins in sphalerite. P. S. 173.

FIG. 2.-Starnite (S) and galena (G) which

altered in part to cerussite (Ce).

166. Oil immersion. X 420.

X 40. veined stannite but is

Wolfram (W). P. S.

FIG. 3.--Molybdenite flake (M) in bismuthinite (B) and quartz (Q), the bismuthinite replacing the quartz along the molybdenite. Note the strong difference in reflectivity between adjacent areas of bismuthinite. P. S. 175.

X 54.

FIG. 4.—Intergrowth of bismuthinite in galena. Crossed nicols. P. S.

235. X 54.

PLATE 10.—Fig. 1.—Galena vein (white) in cassiterite (C). Quartz (Q). P. S.

235. X 180.

FIG. 2.-Chalcopyrite (C) partly altered to chalcocite and covellite, and stannite (S) vein along cleavage in galena. P. S. 166. X 235.

FIG. 3.-Zoning in cassiterite (thin section). Mic. slide 24690.

X 24.

FIG. 4.--Tourmaline (T) replaced by muscovite (M) and chlorite (Ch) in cassiterite (C) and wolfram (W). Mic. slide 24681.

X 24.

PLATE 11.—FIG. 1.-Cassiterite replaced by interstitial felspar. Mic. slide 24680.

X 24.

FIG. 2.-Cassiterite replaced and veined by beryl. Mic. slide 24687.

X 24.

FIG. 3.-Beryl replaced along its cleavage, at walls of scheelite vein.
Mic. slide 24685. X 24.

FIG. 4.-Scheelite replacing platy carbonate. Mic. slide 24683.

X 24.

PLATE 12.—FIG. 1.--Mica veins (M) in cassiterite (C). Note how one of them stops at the border of scheelite (S) after wolfram, and its position in the latter occupied by clear scheelite. Tourmaline (T). Mic. slide 24688. X 24.

FIG. 2. Tourmaline (T) and cassiterite (C) veined by lepidolite (M).

Mic. slide 24698. X 24.

FIG. 3.-Relic quartz in platy carbonate.

Mic. slide 24690. X 24.

FIG. 4.-Platy carbonate. Mic. slide 24696. X 24.

PLATE 13.-FIG. 1.-Wolfram veining muscovite (M) which

interstitial to coarser wolfram (W).
268. X 54.

appears also to be Quartz (Q). P. S.

FIG. 2.-Wolfram (light grey) brecciated and veined by quartz

(dark grey). P. S. 268. X 54.

FIG. 3.—Cassiterite (dark grey) replaced by wolfram (grey). Quartz

vein to left. P. S. 266. X 54.

FIG. 4.-Cassiterite (white) veined and replaced by quartz (grey).

P. S. 265. X 54.

PLATE 14.—FIG. 1.-Fluorite (F) replacing quartz (Q). Wolfram (W) and tungstite (T). Cracks in fluorite, infilled with bakelite, appear like quartz. P. S. 267. X 54.

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