320 An account of the New Jersey Sapphire. 



and white limestone. This bed of white limestone is quite detached 

 and independent of the large bed heretofore described, and a high 

 ridge intervenes between this and that bed. 



The sapphire is blue and white, the central color of a bright ber- 

 lin blue, becoming pale till towards the edge of the mass the color is 

 nearly white. In the feldspar, crystals of the red oxide of titanium 

 commonly occur, of a bright steel gray with a tinge of red, a metallic 

 lustre and translucent at the edges. Smaller masses of sapphire, 

 sometimes in regular hexahedral prisms, are commonly imbedded in 

 a massive rock of slightly yellowish gray hornblende, bearing some 

 resemblance to anthophyllite. Wherever the sapphire occurs, there 

 is a coating or bedding of carbonate of lime, the cellular surfaces of 

 these masses of rock likewise present nests of spinelles of the same 

 curious gray tint crystallized in perfect octahedrons, some of them 

 measuring an inch on each surface of the plane, also occasionally as- 

 sociated with hexahedral copper colored mica ; and now and then 

 masses of large crystals of brown and yellowish brown idocrase, frag- 

 ments of these crystals have occurred from three to four inches in 

 diameter, and prisms a span in length. Steatite is here a common 

 ingredient, and has presented the pseudomorphous form of quartz, 

 scapolite and spinelle. 



The octahedron or steatitive imitation of this last substance is of a 

 pale straw white, and of rather rare occurrence. They project from 

 cavities, and are not imbedded like those we formerly termed pseu- 

 dolite, and which we found at Warwick. In the weathered cavities 

 of the rocks the sapphire often presents a conchoid al appearance 

 arising from the branching and connection of clusters of imperfect 

 prisms, sometimes having two or three sides of the regular prism vis- 

 ible. These masses are not unfrequently imitated by the protean 

 steatite which seems to mould itself to every form. I term this min- 

 eral sapphire rather than corundum, from its beautiful and full color, 

 though it is merely translucent and not transparent, but in this respect 

 it also varies considerably ; very seldom it is white or nearly colorless 

 as well as gray and occasionally also of a blue, as dark as indigo and 

 the more so when imbedded in the feldspar, some masses have been 

 found in this substance of the weight of two and a half pounds. Con- 

 tiguous to the same rock, though not so distinctly connected with it, 

 occur also masses of scapolite in four-sided prisms as large as a man's 

 wrist, and straw colored Brucite, all of which as usual are concomi- 

 tant with the other minerals, and imbedded in the carbonate of lime. 



