Mar. 1899. | THE ORES or CoL_omMpia—NICHOLS, I51 
Massive sulphides of iron and zinc, in irregular branching veins 
in tuff, with crystals of calcite and dolomite. 
‘215. [E 1101.] Ore from Las Vetas mine.” 
Like No, 2:4, 
GOLD AND SILVER MINING DISTRICT OF CARAMANTA. 
Caramanta, nearly upon the southern boundary between Antio- 
quia and Cauca, is upon the western flank of the Cauca valley and 
therefore may be included among the mining districts of the Sierra del 
Choco, or Western Cordillera. 
The ores occur, as nearly as may be judged from hand speci- 
mens, in trachytes and trachyte tuffs like those of the Otramina mine 
of Titiribf. The gangue is, however, calcite instead of dolomite and 
in places it is quartz. Mixtures of quartz and calcite in any quanti- 
ties are not shown in the specimens, however. Antimony in the form 
of stibnite occurs in pockets in the tuff. Associated with the ores, 
according to Sefior Gamba, are dioritic and syenitic porphyries, ande- 
site and phonolite. One specimen in the collection is an altered 
trachyte. 
From Caramanta Sefior Gamba collected twenty-nine specimens 
representing three mines. The series is as follows: 
‘216, Dioritic porphyry.” 
217. Syenitic porphyry.” 
215.) Andesite.” 
‘¢219. Phonolite.”’ 
270. Silver -ore.”’ 
‘¢221. Argentiferous galena.”’ 
‘¢222. [E 1205.] Galena and blende, ore from the Condé 
mine.” 
This is a mixture of galena and yellow blende with a small quan- 
tity of calcite. ; 
gees. | 1200. | Galena and blende from the Condé mine,” 
with calcite and quartz. 
‘¢224. Ordinary ore from the Condé mine.” 
(225. [E 1102.| Blende, ore from the Condé mine.” 
Seams of yellow blende and quartz in andesite. 
’ <€226. Galena, molino ore from the Condé mine.” 
“©228. [FE 1203.] MZolno ore from the Condé mine.” 
*¢229. [E 1103.] Galena, mol/ino ore from the Condé mine.’ 
‘©2230. [E 1104.] Galena, scheiderz from the Condé mine.” 
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