192 PROCEEDINGS OF THE ACADEMY OF [1892. 



Ill Uwchlan Township half a mile north of the Eagle tavern 

 massive blue quartz is found in abundance. Graphite is now being 

 mined quite extensively east of the tavern. 



A number of iron mines were opened in the vicinity of Kimber- 

 ton and Yellow Springs, fifty years ago, and many fine specimens of 

 limonite were found, also a half ton or more of a jet black limonite 

 known as melanosiderite. A. fine specimen of allophane was found 

 in one of the mines near, and is now in the Vaux collection. It is 

 the only one known from Chester County. 



A deposit of limonite was found in West Whiteland Township 

 adjoining the quarry known as Thomas' marble quarry, worked to the 

 depth of 180 feet in the year 1836, and after a few years abandoned. 

 The ore is principally of the variety known as pipe iron ore, but 

 some of it is of a rather different character, for the stalactites or pipes 

 instead of being radiated in structure were "^ composed of concentric 

 layers, making a ^ipe within a pipe. The deposit being of a very 

 limited extent was soon worked out, and now no trace of it remains. 



The following minerals have been found at the Warwick mine 

 holes, at the village of St. Mary's: — magnetite in dodecahedral 

 crystals; actinolite, in small radiated geodes, and a jet black melan- 

 ite garnet in geodes, with a reddish mineral, said to be orthoclase. 



One mile west from St. Mary's are the old Hopewell mines, the 

 ore being magnetite crystallized in octahedrons, with an occasional 

 group of pyrite, and quartz pseudomorph after pyrite. 



One-half mile north from the village of Knauertown are the cele- 

 brated mines known as the Mines of French Creek, being first 

 worked as Keini's iron mine, afterwards as the Elizabeth copper 

 mines ; now being mined for iron. The ore is magnetite mixed with 

 pyrite. Bright pyrite in octahedral crystals with numerous modifi- 

 cations occurs in the vein or wall of calcite; there is also a vein of 

 chalcopyrite adjoining the iron ore vein. The chalcopyrite is crys- 

 tallized where it adjoins the calcite, making the finest specimens of 

 the mineral known to mineralogists. It also occurs in perfect, iso- 

 lated tetrahedra. Besides the above the following minerals occur: 

 calcite crystals, aplome garnet, stilbite, apopliyllite in remarkable 

 specimens, byssolite, erythrite, hornblende and a feld^^par pseudo- 

 morph after natrolite. 



At the lead mines near PhaMiixville, known as the Wheatley and 

 Brookdale mine*, the following have been found:— anglesite, cerusite, 

 pyromorphito, wuU'enite, descloizite, niinietite, galenite, native cop- 



