414 GEOLOGY OF DELAWARE COUNTY. 



MINERAL LOCALITIES OF DELAWARE COUNTY. 



Quartz. (Common.) Abundant throuo:hout the mica slate districts of the County. 



Limpid Quartz. Upper Darbj-, near the Howard House. 



Smoky Quartz. Upper Darby, near the Garrett Road Toll-gate, and also near 

 Kellyville School-house. 



Blue Quartz". Radnor, near the Friends' Meeting-house, and also near Evans' 

 School-house. 



Ferruginous Quartz, found in the honeycomb stone that accompanies the ser- 

 pentine : most abundant in Middletown. 



Amethyst. Aston, near Village Green : and Upper Providence, near the Rock 

 House. 



Green Quartz. This mineral is found at Blue Hill, in small aggregated masses 

 of crystals, some having perfect terminal faces ; also in radiated masses. 



CuALCEDOXY. Found mostly in the honeycomb rock of the serpentine, in Marple, 

 Middletown, &c. 



Jasper. Found as the next above ; generally of a yellow color, and sometimes 

 striped. It is most abundant in Middletown. 



Drusy Quartz. Found as the next above. 



Corundum. Near the Black Horse Tavern, in Middletown. 



Feldspar. (Common.) Abundant throughout the County, in large granitic veins ; 

 of a white color in Birmingham, near the circular line, where it has 

 been quarried and used for making porcelain ; also on Thos. Rees' farm, 

 near Blue Hill; of a green color, at Mineral Hill, in Middletown: of a 

 flesh color, at the old Molybdena mine, on Chester Creek, above Upland. 



Moonstone. Mineral Hill, in Middletown. 



Limestone. (Compact Magnesian.) Radnor, near Morgan's Corner. 



" (Crystalline Primary.) At the old quarry in Birmingham. 



Mica. Generally distributed throughout the County. It has been found in large 

 pieces in Aston, Upper Darby, and Haverford ; in low prisms in Con- 

 cord ; and of a deep rich black color in Middletown, near the Black 

 Horse Tavern ; of a green color, at the old mine, above Upland, on 

 Chester Creek. 



BucKHOLDZiTE. Birmingham township. 



Beryl. In large granitic veins, in the quarries of Chester and Ridley town- 

 ships ; also in Springfield and Upper Darby. 



Chlorite. In nodules from the trap rocks of Upper Darby, where it is granu- 

 lar. It is also found adjacent to several of the exposures of serpentine, 

 where it is slaty. Near Glen Riddle it is scaly. 



Rutile. Edgmont township, in quartz. 



Kyanite. Darby Creek Ferry, where specimens of great beauty have oeen ob- 

 tained ; above the Post road, opposite to the Ferry, where it composes 

 a large proportion of a micaceous rock ; on the farm of Mrs. Pritchett, 

 in Haverford, where it is associated with staurotide in mica slate, and 

 near Darby, on Mount Zion Hill. 



Staurotide. In- Haverford, as mentioned in the next above ; and also in the 

 same township, east of the Friends' xMeeting-house, in decomposed mica 

 slate with garnets. 



Anthophylite. In great abundance near Henry Hippie's, in Marple, and at 

 Castle Rock. Prof. Booth regards thi's mineral rather as Diallage 

 rock. It is found laminated or stratified in Radnor. This mineral is 

 also found near the old lime-kiln in Newtown. 



Actynolite. Generally found associated with serpentine; in Middletown, near 

 the Black Horse Tavern : near Blue Hill, in Upper Providence, and in 

 various parts of the serpentine exposure in Marple and Radnor, but 

 not so abundant. 



Serpentine. See the geological map. It may be found in great variety at an 

 old quarry on the Yellow Springs road. Precious serpentine has been 

 found in this locality. 

 Tremolite. Same localities as actynolite ; and in addition it is found near the 

 old lime-kiln, on the West Chester road, in Newtown. 



