Plate XXX. — Ore Deposits. 



Fk;. 1. Longitudiual section <if' south tl»^i)osit, Moutreal mine. Above tlie main dike rook licli ore 

 is found, wliile Ix'twcen tliis and some smaller dikes is mixed ore. 



Fig. 2. Longitudinal section of north dejjosit, Moutreal mine. Ore is seen above each of two dikes 

 at different depths. The t'ait is noted that ore which was orifjinally Icunid at the surlace 

 and mined in an ojieu ])it has iu both cases been carried under the rock surlace. In this 

 case two parallel dikes, very dose to each other, have, in both cases, above them a moder- 

 ate sized ore deposit. 



Fig. 3. Cross section of south dejiosit, Montreal mine, at No. 8. shaft. The relations of the foot wall 

 qu.artzite, dike rock, cue and drift, are well illustrated. 



Fig. 4. Cross section cd' soutli aud north deposits, Montreal mine, on line of No. 7 shaft of scuitli 

 deposit. The quartzite, both dike rocks of the south deposit, and the dike rock of the 

 north deposit are all seen. 



Fig. 5. Longitudinal section (d' Pence mine. A strong dike carries above it a heavy deposit id' ore, 

 which was reached by two shafts immediately u])on pa.ssing through the drift. Just al>ove 

 this same dike, a little farther to the west, no ore is foiiuil. 



Figs, tj, 7, and 8. Cross sections of Pence mine, at Nos. 1, 2, and Father Henneiiin shafts. The rela- 

 tions of the dike rock, quartzite, ore deposits, drift material, ami fenngluous cherts in this 

 mine-are by these sections clearly shown. 

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