136 MINERALS AND GEOLOGY 



the veins occur in contact with crystalline limestones, these latter 

 contain in many places detached crystals and grains of apatite, with 

 occasional masses of that substance. The most important phosphate 

 region, however, lies on the left bank of the Ottawa, in Buckingham 

 and adjacent townships, where the apatite occurs in the form of large 

 lenticular masses and crystals in broad veins, with pyroxene, mag- 

 nesiari mica (phlogopite), calcite, and other minerals.* Apatite 

 occurs also in connexion with crystalline limestone, associated with 

 fluor spar and octahedrons of black spinel, in the township of Ross 

 in Renfrew county on the Ottawa and with quartz and and calcite, 

 at Calumet Falls. Small shews also are seen in many of the lime- 

 stone bands throughout the Laurentian country between the Ottawa 

 and Georgian Bay. Transparent pink and purple crystals are also 

 reported by Dr. S terry Hunt to occur in association with crystals of 

 augite in a mass of erupted dolerite (see Part III) at St. Roch on 

 the River Achigan. Apatite has likewise been found, in a quartz 

 vein carrying copper pyrites and native copper, with large plates of 

 white mica, in the township of Burford, in the metainorphic district 

 south of the St. Lawrence. 



Finally, it may be observed, small nodular masses consisting in 

 great part of phosphate of lime, mixed with carbonates of lime and 

 magnesia, sand, and other matters, are scattered through a conglom- 

 erate of the (Lower Silurian) Chazy formation at the Allumette 

 Rapids ', and similar nodules occur in limestone strata of the same 

 formation in the townships of Hawkesbury and Lochiel, west of the 

 Ottawa ; as well as in strata of the Quebec group at Point Levis, 

 and on the River Ouelle. These phosphatic nodules present a 

 chocolate or blackish-brown colour, and contain in some cases frag- 

 ments of the shells of Imgulse (see Part IV) and other organic bodies. 

 They are supposed to be coprolites or fossilized excrementous mat- 

 ters. When heated, they emit an odour of burnt animal matter, and 

 evolve ammonia. Phosphate of lime, when converted into super- 

 phosphate by treatment with sulphuric acid, constitutes an agricul- 

 tural fertilizer of the highest value. 



* Crystals of apatite consist most commonly of a simple hexagonal prism with large basal 

 plane, but our Canadian crystals, when unbroken, are terminated by the planes of an obtuse 

 hexagonal pyramid, the basal plane being thus entirely suppressed. This combination has 

 hitherto been only seen in the so-called spargelstein of German mineralogists, from the 

 mountains near Jumilla in the south east of Spain, and in the variety known as moroxite fror 

 Arendal in Norway. 



