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Remember the Rainforest 1

 

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Pieces of entirely minced white quartz, sometimes mixed with loose rock crystal, often accompanied by a white or brown porcelain earth containing iron. The latter, which is called white matter here, is the surest indication of the existence of topaz that appears loose and spread among masses, but more rarely among loose quartz in pieces. The mica finally, yellow-brown and reddish in color, which is commonly called earthy talc, the workers call malacacheta.

Yellow topaz

In it are also the topaz, but less abundant than in those crumbling pieces of gangas; In fact, these stones have been found not only in the softened part of the metal form, but also, as for example in Capao, in the still firm parts. In general, the topaz-containing denim quartz, accompanied by porcelain earth, runs on an earthy talc salbanda, which differs, in color and thickness, from the land near it and which they call formation. The quartz denim, whose main direction, because of the mobility of the whole mass, is not always the same, but while we were there, it ran from midnight to noon, it has a thickness from one inch to two feet. half and over, and is carefully monitored by the workers. Not infrequently it makes large nest-shaped flares, which have hollow quartz but no topaz. The latter are still very rarely found, still in contact with quartzite or with rock crystal; in general they are broken on one side; Of these topazes, with crystalline terminal facets on both sides, we could not find them in the mine. It is a custom of topaz diggers, but inconvenient for crystallographers, that they try to prepare each stone for cutting by breaking the less clean parts with the hammer, and, when the pieces have cracks, they divide them entirely. The size of the stones varies greatly; According to the workers' testimony, fist-sized stones have already been found. The natural color is of various shades, sometimes grayish, sometimes wine-yellow, also of medium color between wine-yellow and flesh-red of different grades, rarely dark red. These stones, when found in the malacacheta, appear to be the lightest. The people also know how to give topaz, through abrasion, an artificial burnt tone, especially a pink-red color. The amount of topaz found here annually is very large, and should amount to between fifty and sixty arrobas; However, these are not always well-cleaned stones suitable for the cut, and even many of them are so unclean in color and so full of cracks that the owners throw them away.

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