148 Fretp CoLtumpian MustEumM—GEOo .ocy, VOL. 1. 
‘(182. [E 1077.] Crystallized pyrites from the Paz level of 
the Zancudo establishment.” 
This pyrite has crystallized as pyritohedrons on altered trachyte 
and massive blende, accompanied by a quartz druse and dolomite 
crystals which run into siderite. 
‘¢783. [E 1652.] Crystallized pyrite from the Paz level of the 
Zancudo establishment.” | 
“©184. [E 1078.] Crystallized quartz and pyrite from the Paz 
level of the Zancudo establishment.”’ 
This is a quartz druse on altered trachyte, with massive pyrite 
and blende. 
‘185. Quartz and pyrite crystals from the Paz level of the Zan- 
cudo establishment.”’ 
“186. [E 1079.] Concentration matte from the Zancudo 
Smelting Works.” 
‘©7187. Slag from concentration smelting from the Zancudo 
Smelting Works.”’ 
“1789. |E 1080.] Rich slag from the Zancudo Smelting 
Works.” 
As these works are conducted according to modern practices, 
these products resemble similar ones of their class elsewhere. 
‘¢tg0, Litharge from the Zancudo Smelting Works.” 
“ror. [E 2841.] Coal from the Zancudo Smelting Works.’’ 
This is a bituminous coal, of the variety known as augenkohle. 
Extensive coal fields are mapped by Reclus in the vicmity of 
Amaga and Sabalétas.* | 
‘‘1g2. Coke from the Zancudo Smelting Works.” 
‘193. [E 1652.] Accretions from the Zancudo Smelting 
Works.” 
The other mines of the Titiribf district are in deposits of a differ- 
ent nature from those just described. They are on narrow dolomite 
veins in agglomerates and tuffs. The agglomerates are formed of 
coarse pebbles with some lava fragments, imbedded in a matrix of 
tuff. The tuffs are fresh in appearance except for an impregnation 
of pyrite. The ore occurs either in narrow veins, usually not exceed- 
ing an inch in width, or in a branching network of still smaller veins. 
The dolomite gangue carries blende and pyrite in quantity. As acces- 
sory minerals, crystallized dolomite, calcite and jamesonite, were 
observed. The latter was in considerable quantity in some of the 
specimens. 


* ‘The Earth and its Inhabitants’: South America, Vol. I, p. 200. 
