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A37

EXCHANGE

AIMBOLIA

v. 73

EARTH SCIENCES LIBRARY

CONTENTS.

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M147742

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135-144

145-156

LIST OF PLATES, VOLUME 73.

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

State.

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

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

FIG. 2.-General view of Aravalli quartzite ridges, Umria, Bariya
State.
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 schcelite (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 X 54.

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

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.

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

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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