A. P. Coleman — Antholite from Elzivir, Ont. 281 



Akt. XXXVIII. — Antholite from Elzivir, Ontario ; by 

 A. P. Coleman, Ph.D. 



An asbestiform mineral occurring in large masses on lots 7 

 and 8, concession 11, in the township of Elzivir, Ontario, was 

 sent to me for determination some time ago by Mr. Blue, 

 Director of the Ontario Bureau of Mines. The specimen 

 consists chiefly of irregular bundles of a strong, fibrous min- 

 eral resembling chrysotile mixed with a dull green one like 

 serpentine, the two passing into one another. The serpentin- 

 ous mineral has evidently been formed from enstatite, since it 

 encloses at one or two places remnants of that mineral on 

 which it has encroached. Small amounts of pale green fibrous 

 talc are mixed with the tough fibrous mineral, and the talc 

 sometimes occurs in small masses by itself. In addition one 

 finds portions of carbonates, partly effervescing with cold 

 dilute acid, and hence calcite ; partly dolomite or perhaps a 

 related carbonate. 



In thin sections under the microscope, the enstatite, which 

 is pale greenish brown with glassy luster, shows the usual 

 characters, prismatic and brachy-pinacoidal cleavage, parallel 

 extinction, and a biaxial interference figure, optically positive, 

 on sections at right angles to the c axis. It is not pleochroic. 

 At the edges the serpentinous mineral appears to have eaten 

 its way inward along the cleavage planes and along a less regu- 

 lar set of fractures at right angles to the upright axis. 



This secondary mineral is colorless under the microscope 

 and shows the faintly polarizing confused mass of scales or 

 vague fibers seen in true serpentine. The fibrous portions 

 have all the appearance of chrysotile, parallel extinction or 

 nearly so, etc. The talc and carbonates have the usual 

 characters. 



Analyses were made of the two fibrous minerals, 1 and 2 

 being of the strong fibers and 3 of the talc, and the results are 

 as follows : 



No. 1. No. 2. No. 3. 



Loss in drying at 110° 1-16 1"44 0'3S 



Further loss on ignition 4-25 9-83 7 - 42 



SiO 2 . _... 55-89 53-98 56-87 



A1 2 3 0-71 (notdet.) o-on 



FeO 6-09 5-61 1 '70 



CaO 2-22 2-14 267 



MgO 29-33 29-52 30-05 



Total... 99-65 99-27 99-18 



