MINERALOGY OF BLACK LAKE AREA. 
37 
Crystallography . 
Only the colourless, or slightly yellowish, crystals from the Montreal 
chrome pit are dealt with in this section ; the specimens collected at other 
localities have the more normal diopside habit, are in general poorly 
crystallized, and present no unusual forms. 
A large number of crystals were measured independently by both 
writers, and upon these there were observed thirty-nine forms ; 1 of these, 
twenty-eight have been previously recorded, while the remaining eleven 
are new for diopside. These forms are given in the following list, which 
also indicates the frequency with which they occur on the crystals. 
1 Seventy-eight forms are listed in Goldschmidt’s Winfceltabellen (1897) and eighty-dx by Zambonini 
(2eits f. Kryst. u. Min.. 46, 1909, p. 39); fourteen additional forms are recorded by Whitlock as having 
been observed up to 1910 (School of Mines Quarterly, XXXII, No. 1, p. 73). 
