GEOLOGICAL SOCIETY OF PENNSYLVANIA. 



311 



times wanting, having left in its former place the hydrate 

 of the peroxide of iron and native gold^ which are seen 

 coating the pseudo-raorphous forms once occupied by 

 the pyrites. Portions of the quartz are very friable^ 

 and like a sponge traversed in every direction by vacui- 

 ties, once filled with the sulphuret, which from some 

 cause has disappeared, leaving the quartz with a rugged 

 drusy structure. This accidental appearance assumed 

 by the quartz is usually considered to be a good indication, 

 and is vulgarly called rotten" or decomposed quartz. The 

 quartz in some of the veins has a pseudo-regular struc- 

 ture, dividing into parallelopipeds. An example of this 

 is observed in the Rappahannock mines. 



Lands containing gold veins within a comparatively 

 small area have been secured for gold mining specula- 

 tions. The majority of operatives have not carried their 

 works to any extent for the want of information. Many 

 of the mines that have been in operation are at a stand 

 for want of the most appropriate plan of separating the 

 gold from the ore. The Rappahannock, the United 

 States, and the Union gold mines are in operation. The 

 plan of operations commenced at the Union is of the most 

 approved practical character, and the issue of the under- 

 taking will materially influence the general prosperity of 

 the gold interests in Virginia. The three engines to be 

 employed in working these mines have been imported 

 from England. The majority of the miners employed 

 here are from the most celebrated mining districts in 

 Great Britain. 



HORIZONTAL BEDS OF FREDERICKSBURG. 



In continuing on towards Fredericksburg, the general 

 appearance of the soil changes. Instead of the red argil- 

 laceous earth that covers the talcose slates, a bluish-white 

 occurs, and the general contour of the hills differs. In 

 approaching Fredericksburg from the south, at about a 



