70 MINERALS AND GEOLOGY 



cobalt and then subjected to ignition (see Part I, p. 35). Warmed, 

 in powder, with hydrochloric acid, it emits an odour of sulphuretted 

 hydrogen. Some of the yellow blendes emit a phosphorescent light 

 when scratched or broken. 100 parts contain (normally) sulphur 33, 

 zinc 67 ; but in the dark varieties a certain amount of iron is always 

 present, and many specimens contain a small percentage of cadmium, 

 manganese, <fcc. 



This mineral occurs with galena in almost all the localities given 

 in the description of that substance, (see under No. 12, above), and 

 lately it has been found in large quantities north of Thunder Bay. 

 Brown and yellow varieties are scattered through all the silver-bear- 

 ing veins of Thunder Bay, and some of the latter have yielded traces 

 of gold, not exceeding, however, 2 dwts. in the ton. Small crystalline 

 masses and grains occur also in most of the lead veins of Peterborough? 

 Frontenac, Hastings, <fec., and some of a wax-yellow colour are occa- 

 sionally seen in fossil shells, or associated with gypsum in small cracks 

 and cavities in the limestone beds around Niagara Falls, as well as 

 in the older limestones of Kingston, Montreal, &c. Zinc Blende is 

 seen likewise in many of the veins of the Eastern Townships, as in. 

 the valley of the Chaudiere, and elsewhere. An auriferous variety 

 is stated by Dr. Sterry Hunt to accompany argentiferous galena, <fcc., 

 in a quartz vein at the St. Francis Rapids on the Chaudiere. 



B. SULPHIDES OF COPPER. 



14. Copper Glance : Dark lead-grey, often with blue or green tar- 

 nish ; streak, black and slightly shining. Crystallization Rhombic, 

 but the crystals have mostly a pseudo-hexagonal aspect. Found 

 commonly, however, in small granular or other masses. H 2.5 - 

 3.0 ; sp. gr. 5.5 5.8. BB, melts with strong bubbling or spitting,, 

 colours the edge and point of the flame green, and yields a globule of 

 metallic copper covered by a dark scoria or crust. One hundred parts 

 contain : Sulphur 20.2, Copper 79.8. 



This ore, often termed ' vitreous copper ore " (although its lustre 

 is perfectly metallic), occurs in small quantities in many of the mineral 

 veins of lake Superior and Lake Huron : as on Spar Island, Pigeon 

 River, St. Ignace, Point Porphyry, Michipicoten, Point-aux-Mines> 

 Batchewahning Bay, Echo Lake, Bruce Mines, &c. It occurs also in 

 many of the copper-ore veins of the Eastern Townships, as in Leeds 

 (at the Harvey Hill and other mines), Halifax, Sutton, Brome, Shef- 





