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kind, in schists of two inches thick, occurring in talcose 
and micaceous rocks. The sulphurs are massive and of good 
quality from Campano, Cumana, and Coro. Asphaltum and 
its varieties are reported to be found on the coasts in great 
deposits and in springs : the specimens in the collection are 
of excellent quality. 
The twelve rock specimens of quartz crystals include - 
some of equal purity and size to those obtained from Brazil. 
The marbles are of inferior quality and quite devoid of 
colour and beauty; but in the International Exhibition of 
1862 some excellent green and red marbles were shown. 
The predominating rocks of the mountain ranges in 
Venezuela are palaeozoic, metamorphosed talcose and clilo- 
ritic slates, with great layers of gneiss ; and within this 
range along the line of faults and in veins, are found an 
endless variety of minerals, of which the collection contains 
asbestos, serpentine, talc, hornblende chlorite, kaolin, felspar, 
and selenite. 
Amongst the comparatively recent rocks are stalactites, 
salt, marl, alum, gypsum, and many calcareous deposits from 
the sea shores and fresh water lakes. 
The special collection made by Mr. Spence during a visit 
to the Island of Orchilla is interesting to the geologist. It 
contains sufficient specimens to decide the main geological 
character of the island to be entirely metamorphic gneiss, 
overlaid with modern calcareous tufas. 
The collection includes a number of crude guanos, phos- 
phates of lime, alumina and urao, a sesquicarbonate of soda 
-—all of commercial value and sources of prosperity if effi- 
ciently worked. 
