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Digging for tourmalines, at least in one locality, offers the fascination that, in some form, seems always present in the mineral industries. One of the earlier sources of supply of tourmalines was Burma, and an interesting description of some of the phases of the quest for tourmalines was written by Mr. C. S. George, deputy commissioner for the Ruby Mine District, Burma, for the London Tribune. Tourmaline, as found there, is in separate crystals in the interstices of granite rock, and men with no capital can mine here and do, in a desultory manner, on the chance of finding more or less valuable bits by digging down a distance of ten feet or less. This was the method of mining at the original ruby diggings at Kathe. The more modern method is that of sinking a vertical shaft four or five feet square. Custom allows the proprietor of the shaft to extend his workings underground anywhere to a radius of five fathoms from the centre of the shaft.
A writer--Mr. C. S. George referred to above--in the Jeweller's Circular Weekly states:
The vein is formed by a vein of white hard granite rock, in the interstices of which the tourmaline is found, at times adhering loosely to the rock, at others lying separate in the loose yellowish earth that is found with granite. When a vein is once found it is followed up as far as possible, subject to the five fathom limit. What, however, makes the mining so exciting and at the same time keeps the industry fluctuating is that the tourmaline crystals are found only intermittently in the vein. One may get several in the length of one yard, and then they will unaccountably cease. Directly one man strikes a vein yielding crystals every one who can commences digging along the line of the vein, but it is all a toss-up as to whether, when the vein is reached, there will be tourmaline therein. Adjoining shafts give absolutely different results, and it is calculated that at least two thirds of the shafts sunk yield nothing at all, while only an occasional one is at all rich.
Of the sixty-two shafts at the time of Mr. George's visit only three were yielding, and of these only one had traces of the best quality stone. The veins are fairly deep down, none having ever been reached at a lesser depth than nine fathoms, while an ordinary depth is forty or fifty cubits. When the "vein" takes a downward direction it is followed as far as possible, but that is rarely over about sixty cubits, for at that depth the foulness of the air puts the lamps out.
All the material dug out from the inside shaft is pulled up to the surface in small buckets, all worked by enormously long pivoted bamboos weighted with a counterpoise, and the tourmaline is sorted out of hand, the granitic fragments being piled in a wall around the mouth of the shaft.
The folk-lore of tourmaline tells us that both the introduction of this beautiful and multiphase mineral to the knowledge and appreciation of mankind, and its discovery in America, were due to children. Soon after the year 1700, some children in Holland were playing in a court-yard on a summer day with a few bright-coloured stones indifferently given to them by some lapidaries, who evidently had not classified, or invested them with any particular value or significance. The children's keenness of observation revealed that when their bright playthings became heated by the sun's rays, they attracted and held ashes and straws. The children appealed to their parents for enlightenment as to the cause of this mysterious property; but they were unable to explain or to identify the stones, giving them, however, the name of aschentreckers or ash-drawers, which for a long time clung to these tourmalines.
The story of the tourmaline in the western hemisphere is an object-lesson for those adults who have no indulgence for the scientific enterprise of the young, or faith in the possibility of valuable results from their immature investigation. The principal source of the best American tourmalines is a mine on Mount Mica at Paris, Maine. Gem tourmalines were discovered on Mount Mica on an autumn day in 1820 by two boys, Elijah L. Hamlin and Ezekiel Holmes, amateur mineralogists. When nearing home from a fatiguing local prospecting expedition, they discovered some gleaming green substance at the root of a tree, and investigation rewarded them with a fine green tourmaline. A snowstorm prevented a further search, but the following spring they returned to their "claim" and secured a number of fine crystals. Tourmalines from Mount Mica are found in pockets in pegmatitic granite, overlaid by mica schist, which has since to some extent been stripped off to facilitate this interesting mineral industry. Black tourmaline, muscovite, and lepidolite are found in this Pine Tree State treasure house. More than fifty thousand dollars' worth of tourmalines have been extracted from the mine resulting from this boyish discovery. While this sum of money is not great in comparison with the financial results of many mineral industries, the output has included very many specimens of rare beauty that have enriched the collections of royalty, wealthy private connoisseurs of precious stones, and of great public museums and educational institutions.
The strong dichroism of the tourmaline and its variety of colour composition and other remarkable properties make it one of the most interesting minerals in Nature's storehouse, and led Ruskin to write in his Ethics of the Dust, in a fanciful effort to describe its harlequin composition:
A little of everything; there's always flint and clay and magnesia in it; and the black is iron according to its fancy; and there's boracic acid, if you know what that is, and if you don't, I cannot tell you to-day, and it does n't signify; and there's potash and soda; and on the whole, the chemistry of it is more like a mediaeval doctor's prescription than the making of a respectable mineral. |
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Precious Stones Guide Vol 4
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