CORUNDUM (SAPPHIRE): OCCURRENCE IN CEYLON 



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The sapphire occurs in Ceylon associated with many other precious stones. The 

 yield of gems of this island is not large, the total value of the annual production being said 

 to be no more than =£"10,000. The locality is, however, remarkable for its variety of gem- 

 stones, namely, sapphire, ruby, topaz, amethyst, cafs-eye and other varieties of quartz, 

 garnet (almandine and cinnamon-stone), zircon (hyacinth), chrysoberyl in its different 

 varieties, spinel, tourmaline, moon-stone, and others which are rarer and of less importance. 

 In association with the precious stones, there are found fragments of common corundum, 

 magnetite, felspar, calcite, &c. Of the above-mentioned precious stones the sapphire is by 

 far the most frequent. 



The precious stones and the minerals with which they are associated were originally, 

 for the most part, constituents of certain granite and gneissic rocks, by the weathering and 

 disintegration of which they have been set free. While 

 the sapphire and garnet were originally embedded in 

 gneiss, other precious stones, such as the ruby and spinel, 

 have been derived from the crystalline limestones (marbles) 

 which are associated with the gneiss. The gems occur in 

 their mother-rocks only sparingly, and are never obtained 

 directly from them, but from the sands, gravels, and clays 

 formed by weathering. These secondary deposits, in 

 which the gems weathered out of the solid rock have 

 been accumulating for long periods of time, are found 

 in the beds of the streams of the present day, and on 

 the sides of the hills above the present high-water 

 level. 



The richest locality for gems is in the south of the 

 island, on the southern slopes of the mountains in the 

 Saffragam district. On this account the principal town 

 of the district has received the name of Ratnapura (or 

 Anarhadnapura), which signifies the " City of Rubies." 

 The occurrence of gems is, however, by no means confined 

 to this one locality, stones being found in the western 

 plain between Adam's Peak and the sea, near Neuraellia, Kandy, Matella, and Ruanwelli, 

 and in the river-bed of the Kalany Ganga near Sittawake, six miles east of Colombo. Also 

 near Matura, on the south coast of the island, and in the rivers on the east in the neigh- 

 bourhood of the Mohagam river. The localities specially rich in sapphires are the Saffragam 

 district and the neighbourhood of Matura, where a considerable number of stones of large 

 size and fine quality are found. 



The gem mines near Ratnapura were visited and described by Ferdinand Hochstetter, 

 during the voyage of the Austrian frigate Novara. iThey are situated on the Kalu 

 Sella, a small tributary of the Kalu Ganga, partly in the bed and partly on the right 

 bank of the river. The mines, which reach a depth of 30 feet, were not being worked at 

 the time of Hochstetters visit, and were filled with water. The uppermost layer is a thick 

 yellow clay with nodules of limonite resembling our boulder clay in appearance. Below lies 

 unctuous black clay and clayey sand ; then bituminous clay enclosing abundant plant 

 remains, the teeth and bones of elephants, &c. ; then sand, and finally a bed of pebbles with 

 red, yellow, or sometimes blue clay. This constitutes the gem layer, and is known as the 

 stone-gravel or " malave." The gems are found mainly between the large pebbles ; they 

 ai-e specially abundant when the layer contains a greenish, talcose, partly decomposed mica. 



Fig. 59. Occurrence of sapphire in Ceylon. 



