GEOLOGY. 303 



are broken at the surface of the quartz, while others are wholly in- 

 cluded in it, terminating in a single plane, or tapering to a point. 

 They are all of a uniform bright reddish-brown color, and of the lus- 

 tre of polished copper. Where the ends are seen on the polished faces 

 they have the color and lustre of polished steel. In some specimens 

 there are numerous, vermiform, tortuous, and convoluted crystals. 

 They occur either singly or in groups of several laterally joined, and 

 united in all their convolutions, and having a single terminal plane, 

 highly lustrous, which often presents a silver-white color. These 

 crystals, Prof. Hubbard conceives to be chlorite. 



If these several minerals were at one time in the fluid quartz, they 

 must have crystallized previous to it. The rutile prisms are so straight, 

 or so gracefully curved and bent, that they would seem to have expe- 

 rienced but slight resistance. They intersect and cross each other 

 and pass through the loops in the chlorite crystals, or touch them upon 

 the outside, and they probably crystallized first. Around most of these 

 convolutions of the chlorite, there is a burr, or a minute spot of im- 

 perfectly radiating fractures, which suggests that they were formed, 

 before the solidification of the quartz, and that they had occasioned 

 some pressure or disturbance, and a slight fracture. But as the chlo- 

 rite uniformly, and the rutile in very many cases, must have been 

 without any attachment, the density of the fluid quartz to have sus- 

 tained them was probably great. There must be somewhere, in this 

 region north, a rich deposit, for which mineralogists will earnestly 

 seek, until it is found and its treasures transferred to their cabinets. 

 Prof. Hubbard, before the American Association. SiUimaris Journal, 

 Nov. 



MINERAL PHOSPHATE OF LIME. 



MR. ALGER announced to the Boston Society of Natural History, in 

 December, the discovery in New Jersey of a valuable and extensive 

 deposit of massive phosphate of lime. It occurs in the town of Hurds- 

 ville, Morris County, a few miles from the Morris Canal, and is asso- 

 ciated with magnetic iron pyrites, and rarely with copper pyrites, all 

 together forming a vein of about eight feet in width, traversing a gneiss 

 or hornblende rock. These metallic sulphurets occupy the lowest part 

 of the vein, but are often penetrated by the inter-crystallization of the 

 phosphorite, which is sometimes met with in very regular prisms of 

 the usual hexahedral form, and several inches in length, entirely sur- 

 rounded by the metallic gangue. The superincumbent portion of the 

 vein, of about 5 feet thickness, is composed entirely of the massive 

 and semi-crystalline phosphate, and it follows the lower portion with 

 a pretty uniform dip and parallelism to the depth of about 30 feet, as 

 far as it has been explored. It extends to the surface of the ground, 

 and was opened for the purpose of obtaining pyrites for the manufac- 

 ture of copperas, or green vitriol, which it was thought would pay the 

 cost of mining, while the phosphate of lime was overlooked, or sup- 

 posed to be some common rock, though the occurrence of a few crys- 

 tals of the mineral, imbedded in the pyrites, had been known for some 



