610 



Report of the State Geologist. 



on the strike and of depth not visible, as it is full of water. The wall rock is 

 massive dark anorthosite, practically pure labradorite A line of strong 

 attraction runs north and south along the east side of the Adirondack river. 

 There is a little show of ore where it crosses Calamity brook, but the amount 

 visible is not great. I was informed by Mr. Buttles, who was in charge of the 

 'club house, that it had been opened at the north, where the word iron-ore 

 appears on the map. The "Iron Dam," so widely known in connection 

 with the region, crosses the river just above the present club house, and 

 shows as a black strip, striking approximately N. 25° E. The ore is more or 

 less mixed with anorthosite and appears to be an integral part of the rock. 

 In the rear of the ice houses that stand to the west and ;i short distance back 

 of the club house, there are openings on another body of ore which is revealed 

 in a small excavation. A breast several feet across is exposed. The strike is 

 somewhat indefinite, but the ore bears westerly into the hill. 



This entire belt of ore along the river may perhaps be considered as a 

 single one of many individual masses. The ore afforded was called " Black 

 Ore," and the name is still perpetuated on the map given above. Professor 

 Emmons regarded the belt as essentially a single one with many individual 

 masses separated by intervening walls of rock. He also states that 

 hypersthene, labradorite and small masses of serpentine" were the only 

 foreign admixtures. It is of mineralogic interest that he cites one or two 

 inclusions of pyrites, the size of a butternut, for sulphides are very rare in 

 titaniferous ores. Professor Emmons o-ives the extreme width of the belt as 

 over 700 feet, and its length as 3,168 feet. Its general character of large 

 masses in the midst of wall rock which is also massive, lends itself to an 

 interpretation of igneous origin with greater readiness than to any other. 

 Great quantities of ore were obtained from the float for the early furnace. 



Ore from the Millpond opening was largely used by Mi'. Rossi in his 

 experimental run, and several analyses have been published by him to which 

 are added two that I have received directly from him. The analyses show 

 that the percentage in titanic acid is quite variable, ranging in round numbers 

 from ten to twenty. The percentages in iron hold at very good values, and 

 the phosphorus and sulphur are extremely low. The alumina and silica are 

 in small amount in the first two and suggest the presence of labradorite, but 

 the high alumina of the third is difficult to explain on any other supposition 

 than that some form of spinel is in the ore. Titaniferous ores high in alumina 

 have been met in Westport township, and the same inference is still more 

 strongly suggested by them. 



