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MEMOIR ON EMERY.
Communicated to the Academy of Sciences of the French Institute, July, 1850.
ON THE GEOLOGY AND MINERALOGY OF EMERY FROM OBSERVATIONS MADE IN ASIA MINOR.
Of all the mineral substances employed in the arts few have offered so little opportunity for geological examination as emery, and consequently our knowledge of it in this particular is very limited.
Aware of the importance of the study of this substance in situ, both in a scientific and practical point of view, I did not lose the opportunity afforded by my late position under the Turkish Government to develop certain facts that came under my notice the latter part of the year 1846. Prior to that period emery (which term is here used, as in the arts, to express that mixed granular corundum employed for abrasion), although known to exist in many places in greater or less abundance, was supplied to the arts almost entirely from the island of Naxos in the Grecian Archipelago. So true is this that the proprietors of the mines in that island controlled completely the price of this mineral. The emery from Naxos frequently went under the name of Smyrna emery, from the fact of its coming to us from that port, where it is originally carried from the island for future exportation.
Prior to 1846 the existence of emery was not remarked in Asia Minor or any of the contiguous islands except that of Samos, which fact is alluded to in Tournefort's travels in the seventeenth century. In the latter part of 1846 I arrived in Smyrna, and was shown specimens, which I recognized as emery, that came from a place about twenty miles north of Smyrna;
they had been first discovered through the agency of a knifegrinder of the country, who had been in the habit of using it to charge his wheels with. The importance of this circumstance to the Turkish Government, as well as to the arts (emery being at that time sold at a most exorbitant price), induced me to return to Smyrna in the early part of 1847 for the purpose of examining the supposed locality of this mineral. On this second visit other localities were made known to me that an English merchant by the name of Healy had succeeded in bringing to light.
The first locality toward which I directed my examination was that of Gumuch-dagh, a mountain about twelve miles east of the ruins of Ephesus. Before, however, arriving there I discovered this mineral imbedded in a calcareous rock in a valley twenty miles south of Smyrna, called Allahman-Bourgs. The position not being very favorable for the study of the geology of this substance, my route was continued to the place originally fixed upon. Obtaining guides at the village of Gumuch, I commenced the examination of the mountain, which is composed of bluish marble resting on mica-slate and gneiss. On the very summit of the mountain the emery was found scattered about and projecting above the surface of the soil. After examining the extent of the formation and satisfying myself that it was there in situ, I returned to Constantinople and made a report to the Ottoman Government. Although I gave no notice to the scientific world of the result of my examination, the editor of the Journal de Constantinople inserted a small note in his journal, in May, 1847, to the following effect: "It is some time since M. Lawrence Smith, American mineralogist, discovered at Magnesia, near to Gumuch-Kuey, an emery-mine, of which he brought specimens to Constantinople. The government have sent to the place a commission composed of Mr. Smith and some of the officers of the imperial powderworks to examine thoroughly into the importance of this mine, and according to the report that will be made the government will decide on the steps to be taken with reference to it," etc.
This circumstance, unimportant in itself, has subsequently become of great value to secure to me the priority of the discovery and examination of emery in situ in Asia Minor, and also to show that I have been instrumental in the development
which has been subsequently given to this emery in a commercial point of view. Since the first discovery other localities have been ascertained by me, all of which will be alluded to in this memoir.
LOCALITIES OF EMERY IN ASIA MINOR AND THE NEIGHBORING
Gumuch-dagh. In going from Ephesus east to GouzelHissar (the ancient Tralles) we pass by the ruins of the ancient city of Magnesia on the Miandre, and near to this latter is a beautiful valley, celebrated for its figs, in which is situated the village of Gumuch at the foot of a mountain bearing the same name. It was here that the emery formation was first examined. All the rocks of the surrounding country appear to belong to the old series; the limestone is entirely devoid of fossils and metamorphic in its character; it rests on the older schists, of which mica-schist appears the most abundant, and this again farther to the north was traced in contact with gneiss. The limestone is of a light-blue, passing into a coarse-grained marble, and on the south side the rock by its decay leaves in many places precipices of considerable elevation that add much to the picturesque appearance of the region.
The emery is found in different places in the Gumuch Mountain; the place, however, to which it is traced in greatest abundance is on a part of the summit about three miles from the village of Gumuch, and some fifteen hundred or two thousand feet above the level of the valley; it overlooks the magnificent plain of the Miandre, whose curiously tortuous, course is seen as if traced on a map. The emery lies scattered on the surface in the greatest profusion, in angular fragments of a dark color, and large masses of several tons' weight are seen projecting above the surface; in penetrating the soil the emery is found imbedded in it, and a little farther down it is come to in the rock. In fact, by breaking the marble that projects above the surface at this spot, we are sure to find nodules of the mineral.
Sometimes the emery forms almost a solid mass several yards in length and breadth. One of these places, opened for the purpose of exploring, is about ten or twelve yards square, and all the rock taken out is emery; the spaces between the
blocks are filled with an earth highly charged with oxide of iron. In some places the masses are consolidated by carbonate of lime of infiltration, which must not be confounded with the emery in its original gangue (the marble), in which it is found in nodules sometimes round and at other times fissured so as to represent angular fragments. In no place does it present any thing like a vein, nor has it signs of stratification. The largest mass at this locality that I saw unbroken must weigh from thirty to forty tons.
Attached to this mineral, more especially in the fissures and on the surface, are several minerals that will be alluded to hereafter.
Kulah. This locality of emery is the second in importance in Asia Minor. It is a town situated about a hundred and fifty miles from Gumuch and twenty miles from the ancient city of Philadelphia (one of the seven churches). It is near the river Hermes, and on that interesting volcanic district of Asia called Catacecaumene, or the burnt country, resembling in many respects the volcanic region of Auvergne. The rocks forming the base of this region are of the older metamorphic series, covered to a greater or less depth by lava of different volcanic periods, which has flowed from the numerous craters that form the prominent feature of this region. The most common rocks in the mountain ranges about Kulah are white granular limestone, mica-slate, hornblende-schist, gneiss, and granite; the last four are seen more conspicuously in the mountain two or three miles to the south, which have not been subjected to volcanic action; the limestone overlies these rocks.
Before arriving at the place where I examined the emery (about two miles to the northeast of Kulah), an outcropping of gneiss was seen and subjected to the closest scrutiny without discovering the slightest trace of corundum; and I will here remark that although I have found several thin layers of micaschist engaged in the marble, in no instance was there any trace of corundum in it.
The marble in this region is very compact, of great hardness, and I may also add of great purity. I can not say whether this hardness is traceable to a greater depth than that to which it has felt the influence of the superimposed lava.