80 B, J. HARRINGTON ON SOME 
attention to a mineral supposed to have been found in the Townships of Elzevir and 
regarded by him as perhaps a mixture of antimony glance with zinkenite or jamesonite.* 
The mineral from Barrie, however, cannot consist of such a mixture, as is evident from its 
high specific gravity. 
TENNANTITE. 
The mineral here referred to tennantite occurs at the Crown Mine, Capelton, P.Q., 
associated with copper pyrites, iron pyrites, quartz, etc. It is massive, has a brilliant 
metallic lustre, dark lead-grey. colour, and dark reddish-grey streak. The hardness is 
about 4, and the specific gravity 4.622. Before the blowpipe on charcoal it usually 
decrepitates and fuses easily to a black magnetic globule, from which metallic copper 
separates after blowing for some time. Arsenic, antimony and zinc coatings are also 
deposited upon the charcoal. The mineral is very brittle and uneven to subconchoidal in 
fracture. 
According to Tschermak the composition of tennantite may be expressed by the for- 
mula 4 Cu As 8, 3 Cu, 82 FeS., and with this the mineral from Canada agrees closely, except 
in the partial replacement of arsenic by antimony and iron by zinc. As in the case of the 
meneghinite, the mineral was decomposed by chlorine, according to the admirable method 
of Rose, and the percentage composition found to be as under L., the composition deducible 
by the above formula being given under II. 



i JU 
| == 
Sulphur................... 27.99 28.5 
Arsenic.-...... ala: tr 15.34 20.5 
ATHMONVEE- er door AO ||” Yelslere 
Copper e-.--ne-s-cr-r--ee 42.09 | 43.4 
| Ioitoaodondo00e0ocooa onto OUR UT ot 
| PinCrereceetecel 2190000800 4.56 | 
\ Blbeadisac ss ttene steerer tte 25 | | 
Gilworee-eneaso: berate ty were | 
| Undecomposed............ -09 oo 
| | 
| 98.82 | .... 




No tin was detected, but inasmuch as that metal was not long since found in frederi- 
cite, a variety of tennantite from Sweden,* the writer's intention was to make further 
examination for it. Owing to want of time, however, this has not been done. 
Whether tennantite occurs at any other of the copper mines in the Townships I am not 
aware. A “ dark steel-grey foliated ore,” occurring at Harvey Hill, was many years ago 

* Minerals and Geology of Central Canada, 1871, p. 84. 
+ For his specimens the writer is indebted to R. G. Leckie, Esq. 
* H. Sjogren (Geol. Für. Forh., V., 82, 1880). 
