PHYSIOGRAPHY. 245 



Tourmaline. 



4. Tourmaline is frequently met with in rocks, particularly in gran- 

 ite, but without forming a regular ingredient of any, and is found im- 

 bedded in them in larger or smaller masses, or crystallized in the drusy 

 cavities, as in the Topaz-rock of Saxony and the granite of Paris, (Me.) 

 The dark brown variety of Monroe, (Conn.) forms with Mica a bed in 

 mica-slate. The cinnamon-red occurs disseminated through dolomite 

 and granular limestone ; and the green and red varieties with smoky 

 Quartz form a vein embraced on each side by Albite, traversing granite 

 at Chesterfield, (Mass.) It is also met with in the shape of pebbles, in 

 the stream-works, and in the san4 of many rivers. 



5. Some of the most remarkable among the foreign localities of Tour- 

 maline are the following; black crystals in Greenland, in the mountains 

 called Horlberg near Bodenmais in Bavaria, and near Bovey in Devon- 

 shire, England; red varieties from Perme in Siberia, Rozena in Mora- 

 via; pale green with a tinge of yellow at St. Gothard in dolomite, and 

 green and blue varieties from Brazil and Ceylon, where they are found 

 in the sand of rivers. 



The United States is particularly rich in Tourmaline. Paris, (Me.) 

 has thus far yielded the most remarkable crystals for size, color 

 and transparency, and which were found loose in the soil, covering a 

 decomposing ledge of graphic granite. Some of these were upwards of 

 an inch in diameter, transparent, red at one end and green at the other. 

 The granite still continues to afford blue and pink crystals and compound 

 varieties, which are mostly imbedded in Lepidolite; also long slender 

 green crystals and columnar aggregations traversing large individuals 

 of brown Mica. The vein of Tourmalines of Chesterfield, (Mass.) is 

 about one foot in width. The crystals are small, rarely perfect in form, 

 deeply striated, often much curved, and rifted by cross seams into which 

 the Quartz is thrust. The green crystals especially those situated in 

 the smoky Quartz, often contain in their centres prisms of Rubellite, 

 while the single crystals of Tourmaline which have shot into the Al- 

 bite, are frequently pure red or green. Similar varieties are found at 

 Goshen, where the interior of the crystals is sometimes blue or green, 

 and the exterior a pale rose-color, or some different shade of green or 

 blue. The deep indigo-blue varieties, particularly, abound at Goshen. 

 Monroe, (Conn.) furnishes the most perfect crystals in form, found in 

 the United States. They are of a dark yellowish brown color, and trans- 

 lucent only on their edges. They vary in size from a hazle-nut to two 

 or three inches in length, and one or two in diameter, being universally 



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