Canadian mining journal July-December 1915 . s distinguished from thefissure vein and contact lode types, this sort ofvein finds its sole representative in the PorcupineCrown Mine. Here, the orebody, which appearsto have been somewhat contorted by subsequentpressure, follows approximately the contact of aquartz prophyry stock with the older volcanicseries. It does not lie along the contact at allpoints, since this is extremely irregular, but it con-forms to it as well as a single fissure could, cuttingacross both promontories and embayments in themargin of the intrusive mass. As tentatively be
Canadian mining journal July-December 1915 . s distinguished from thefissure vein and contact lode types, this sort ofvein finds its sole representative in the PorcupineCrown Mine. Here, the orebody, which appearsto have been somewhat contorted by subsequentpressure, follows approximately the contact of aquartz prophyry stock with the older volcanicseries. It does not lie along the contact at allpoints, since this is extremely irregular, but it con-forms to it as well as a single fissure could, cuttingacross both promontories and embayments in themargin of the intrusive mass. As tentatively be-lieved by the management, the channel in whichthe vein formed by replacement of the channelwalls seems to have been a tension rupture, dueperhaps to the contraction of the intrusive stockon cooling. Contact Lode The most studied andperhaps the best representative of this type of de-posit is the contact vein of the Mclntyre was most typically developed where mined instopes Nos. 317 and 117, north and north westof No. 4 ^ icw showing Itunded Slructurc at Margin of Vein, indicatingMet atom at ic ( im w th of Ore hod v . Mclnt\rc Mine This body consisted of a mineralized zone alongthe contact of the basaltic schists with the southwall of the quartz-porphyry stock underlying PearlLake. In this zone were usually many veinlets ofquartz, sometimes coalescing and again or perhaps even dwindling in size andnumber until the quartz constituted only a smallproportion of the unliable material. The schist inthis zone was usually impregnated with finelyt rystaline auriferous pyrite and free gold, while the
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Keywords: ., bookcentury1900, bookdecade1910, booksubjectminesandmineralresou
