344 M. Beudant on the Opals of Hungary. 
Pitchstone ; although this expression has been exclusively re- 
stricted by Werner to vitreous substances, with a somewhat 
greasy lustre, which, like obsidian, approach to the nature of 
felspar. The powder of these varieties is rust brown ; and when 
one has broken several specimens, his hands become tinged just 
in the same way as if he had been touching certain kinds of 
earthy iron. In some parts of the kidneys, nests occur entirely 
formed of pulverulent oxide of iron, which are easily detached, 
and which leave irregular cavities, sometimes divided by partitions 
of jasper. Sometimes the entire mass is of oxide of iron, or of 
ochraceous matters, which are found here and there penetrated 
by the opaline siliceous matter. These masses are, in some parts, 
sufficiently considerable to be wrought as ores of iron, which is 
the case, for example, at Kendereske, not far from Munkacs, in 
the county of Ungh, where the mass is also accompanied with 
a particular green earth, in which veins of opal-jasper equally 
occur. The iron ores of Zamuto are in the same situation ; and, 
perhaps, also those of Domonya, near Unghvar ; it appears that 
there are similar ones in many other places, 
Opal-jasper, whether pure or mixed with oxide of iron, some- 
times loses by little and little the resinous lustre which common- 
ly characterises it, and passes, by insensible gradations, into com- 
mon jasper, which then presents various colours, whitish, yellow- 
ish, greenish, blood-red or crimson-red, the fracture being more 
or less conchoidal. It passes also into calcedony and hornstone. 
It is also asserted, that beautiful carnelians have occasionally 
been found in the same places. These varieties are much less 
abundant than all the others ; but they occur precisely in the 
same matrix, and in the same localities, where they only form se- 
parate nests. 
We have already seen, that the opals sometimes occur in a 
soft state. I have not directly observed this state in the opal- 
jasper ; but its occasional existence is sufficiently indicated by 
many circumstances. In fact, I have often found kidneys or 
veins of this substance, which presented the characters of a 
desiccated gelatinous matter, precisely similar to the desiccated 
gelatinous silex of our laboratories. The numerous and large 
chinks which these masses presented in their natural position, 
those which are still manifested in the specimens which I have 
