. Bulletin of the Geological Society of America. Geology. OBJECTIONS TO LIQUATION HYPOTHESIS. 127 VN^ ^^^ v>s*> ^ VV V OsV't-v' occur as a result of primary diJEferentiation, then it would frequently characterize intrusive masses, either with or without the presence of a gneissic structure. The absence of observations in support of this is proof presumptive that it does not exist. 3. The relation of the ellipsoids and pyroxene bands to the inclosed apatite crystals and masses. Their concentric arrangement about the apatite indicates that the formation of the apatite antedated the develop
. Bulletin of the Geological Society of America. Geology. OBJECTIONS TO LIQUATION HYPOTHESIS. 127 VN^ ^^^ v>s*> ^ VV V OsV't-v' occur as a result of primary diJEferentiation, then it would frequently characterize intrusive masses, either with or without the presence of a gneissic structure. The absence of observations in support of this is proof presumptive that it does not exist. 3. The relation of the ellipsoids and pyroxene bands to the inclosed apatite crystals and masses. Their concentric arrangement about the apatite indicates that the formation of the apatite antedated the development of the gneissic structure. The difficulties in the way of considering that the formation of the apatite deposits took place in the original magma are: a. Their large size. The deposits vary from a few inches in cross-section to several feet, and often extend many feet in horizontal and vertical directions. The crystals are frequently several inches in diameter. The larger crystals usually occur in pockets in the pyroxenite, associated with pink calcite, mica, etcetera. A crys- tal obtained at the Emerald mine, on the Du Lievre, and exhibited at the London Exposition in 1886, measured 62J inches in circumference and weighed 550 pounds.* Crystals one to two inches in diameter frequently occur in the granular deposits. In pit number 11 at High Rock, a crystal five or six inches in diameter was observed in an inaccessible part of the wall imbedded in the ellip- soidal rock. b. Their inclusions. Doctor Hunt noted rounded crystals of quartz and carbonate of lime as inclusions in the apatite, t Similar observations were made by Emmons, J while Harrington states! that the apatite crystals fre- quently inclose calcite, pyroxene, phlogopite, zircon, sphene, fluorspar and pyrite. While it cannot be posi- tively asserted that these inclusions characterize the crystals imbedded in the ellipsoidal rock, the correspond- ence between these crystals and the other deposits as to their occur
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