CALCITES OF NEW YORK 79 
and groups. In all about 6 tons of material of exceptional beauty and 
interest were taken from this locality. 
In habit the calcite crystals resemble those from Rossie, St Lawrence 
co., a locality situated about 20 miles northwest of Sterlingbush and in a 
limestone area similar in character, age and general trend. 
The basal pinacoid 0 (0001), which is universally present, is strikingly 
developed on all the larger crystals. The planes of this form are smooth, 
of medium brilliancy and covered, in many instances, by triangular pits 
produced by a tendency to form parallel grouping. The rhombohedron 
‘p.(1011) is also universally present but unequally developed. In some 
instances, as in the case of the larger crystals, it becomes the dominant form 
producing a distinctly rhombohedral type. A series of scalenohedrons in 
the zone [1011:0112] bevels the lateral edges of the primative rhombohedron. 
This series in the above mentioned zone tends to reflect the goniometer 
signal as a broad band, some 9° in width, from which specially luminous 
points were selected and the readings repeated on 17 of the most brilliant 
of the smaller crystals. These luminous points correspond to the scaleno- 
hedrons K:(2131), H:(9.5.14.4), N:(6382) and P:(8251). Considerable 
vicinal development mars the sharpness of these forms and gives to the 
zone between these limits a somewhat rounded aspect. On one crystal 
two faces of the scalenohedron T (4261) were found, developed to considerable 
brilliancy and sharpness. This crystal is shown in figure 1, and may be 
taken as an average expression of the habit of the larger crystals. Figure 2 
shows:a crystal of scalenohedral habit typical of the calcite incrusting the 
roof and walls of the outer cavern. These average from 1 to 4 centimeters 
in vertical length and show in addition to the forms already mentioned the 
negative rhombohedron ¢.(0221) developed as a series of small brilliant planes. 
The large crystals show a strong tendency toward the formation of 
penetration twins parallel to a composition face 0. This twinning habit 
finds expression in deep reentrant angles or “ channels,’ well shown in 
figure 4, and produced by-corresponding planes of p.(1011) in twinned 
position. 
