Pyroxenes. 15 



pression where the apex of the pyramidal faces should be, while the 

 pyramidal planes meet in a rounded edge about the depression. 



The inclusions of quartz are confined exclusively to graphite. 

 This latter mineral occurs gashing the quartz iu the same way as it 

 does the pyroxene. 



Of the graphite but little need be said as in appearance it differs 

 but little from the ordinary occurrence. Disseminated through the 

 bodies of other crystals it occurs in the usual six-sided tablets. There 

 is one form, which is quite frequent here, which Dana's Min- 

 eralogy describes as of rare occurrence. This is the radiated, glob- 

 ular mass. These globules, the size of a buckshot, have been 

 found by Mr. Beecher and myself, and there are specimens of them 

 in the Museum at Albany. They have not been found except in the 

 calcite. The tablets enclosed in the calcite cut the prisms at all 

 angles, and even when lying approximately parallel to any face, the 

 graphite is apt not to lie in one plane, but to have a warped surface. 



The scapolite group is represented by a mineral which is assumed, 

 pending analysis, to be wernerite. It occurs in the usual simple 

 form, but rarely with rounded angles. Microscopic sections show 

 infiltrated veins of radiating chalcedony. Nearly all specimens are 

 more or less decomposed. Apatite occurs here in such small quan- 

 tities as hardly to deserve notice, yet, on account of its presenting 

 the same "fused" appearance as the other minerals, it is mentioned. 

 It has the same light green color as nearly all of the apatites found in 

 the Laurentian limestones. About the same degree of transparency 

 also obtains. In form they have the simple prism and pyramidal 

 faces with the O-faces occasionally developed. They vary in size 

 from crystals a foot in length with a diameter of from one to two 

 inches, to slender crystals one-eighth inch in diameter and from one 

 to two in length. The crystals occur usually in the calcite but are 

 sometimes found modifying and being modified by contact with 

 quartz and pyroxene. The mineral differs in this respect from all 

 others noticed, in the fact that however irregular or "fused" its 

 surface may appear it is always with a perfect polish. 



Sphene occurs in crystals never more than one-half inch in length 

 and of the usual simple form. Its occurrence is limited to the com- 

 pact masses of pyroxene, or where pyroxene, calcite and graphite are 

 intimately mingled. 



It remains now to mention the calcite which occurs here. It is in 

 reality the "veinstuff" or gangue of the mineral sought as well as 



