492 



MINERALOGY. 



Oryctogno- appearances of this kind hitherto observed in Scotland 

 7 and England. But the most celebrated staluctitic cave 



x-> ^r**' is that of Antiparos in the Archipelago, which has 

 been particularly described by Tournefort. Similar 

 caves occur in Germany, France, Switzerland, Spain, 

 in the United States of America and other countries. 

 Italy, which is so rich in fine marble, is not less so in 

 beautiful calc-sinter or calcareous al-ibaster ; the t rri- 

 tory of Volterra in Tuscany alone furnishes no fewer 

 than twenty different varieties. Sicily is also abundant 

 in calc-sinter ; and of these, the rose-coloured variety 

 of Trapani is much admired. Spain is, next to Italy, 

 the most productive country of calcareous alabaster. 

 The environs of Granada and Malaga are particularly 

 remarkable for the beautiful varieties of this mineral 

 which they afford. Persia also abounds in highly prized 

 varieties of calcareous alabaster. 



Uses Calc-sinter or calcareous alabaster, is used 



for the same purposes as marble, and is cut into tables, 

 columns, vases, drapery for marble figures, and some- 

 times also into statues. It was also used by the ancients 

 in the manufacture of their unguentary vases. 



SIXTH SUBSPECIES. 



Tufaceous TuFACEOtJS LlMESTONE CALC-TUFF*, JameSOH. 



limestone. Kalk-Tuff, Werner. 



External Chat acters Colour yellowish-grey, which 

 sometimes approaches to ochre-yellow and yellowish- 

 brown. Occurs massive, perforated, ramose, spongy, 

 tubular, claviform. botryoidal, globular, cellular, and in 

 crusts ; enclosing vegetable stems and leaves ; also 

 bones of animals, as of elephants and rhinoceroses, and 

 land shells; and also with frequent impressions of 

 leaves, mosses, and roots. The globular variety is 

 sometimes composed of curved lamellar concretions. 

 Internally dull, or very faintly glimmering. Fracture 

 fine-grained uneven, inclining to earthy ; and some- 

 times splintery. Fragments indeterminate angular. 

 Opaque, or translucent on the edges. Sometimes semi- 

 hard, sometimes soft, and is frequently soft, inclining 

 to friable. Rough. Brittle, and easily frangible. 



Constituent Parts It is nearly pure Carbonate of 



Lime. 



Geognostic Situation It occurs in beds, generally in 



the neighbourhood of lakes and rivers : also encrust- 

 ing rocks, and enveloping animal and vegetable remains 

 in the vicinity of calcareous springs. 



Geographic Situation It is a frequent mineral in the 

 neighbourhood of all the calcareous springs in this 

 country, as in those at Starly Burn in Fifeshire, and 

 other places ; and on the Continent of Europe it is also 

 a frequent mineral. 



Uses. The hardest kinds are used for building- 

 stones, and are also burnt into quicklime. It is some- 

 times also used as a filtering stone. 



SEVENTH SUBSPECIES. 



Pisiform PISIFORM LIMESTONE, or PEA-STONE, Jameson. 



limestone. Erbsenstein, Werner. 



External Cliaraclers, Its most common colour is 

 yellowish-white, which sometimes approaches to snow- 

 white ; from yellowish-white it passes into pea- 

 yellow, and pale-yellowish brown. Occurs massive; 

 also in distinct concretions, which are coarse, small, 

 and very seldom fine spherical round granular, com- 

 posed of others which are very thin and concentric 

 lamellar. In the cent e there is either a bubble of air, 

 or a grain of sand, or of some mineral matter. Inter- 



nally dull, or very feebly glimmering. Fracture even. Oiyctogno- 

 Fragments indeterminate angular, and blunt-edged. 1 * v ' ^ 

 Opaque, or feebly translucent on the edges. Soft, ap. ^"f~^ 

 proaching to semi-hard. Brittle, and very easily fran- 

 gible. Specific gravity 2.532. 



Constituent Parts It is carbonate of lime, slightly 

 coloured with iron. 



Geognostic and Geographic Situations. It is found 

 in great masses in the vicinity of the Hot Springs at 

 Carlsbad in B< hernia. 



Uses It is sometimes cut into plates for ornamental 



purposes. 



EIGHTH SUBSPECIES. 



SLATE-SPAR, Jameson Schieferspath, Werner. Slate-spar. 



ExternalChaiacters Colours greenish-white, reddish- 

 white, yellowish- white, greyish-white, and snow-white. 

 Occurs massive, also in distinct concretions, which are ge- 

 nerally curved lamellar, and sometimes coarse and large 

 granular. Lustre intermediate between shining and 

 glistening, and is pearly. Fragments either indeter- 

 minate angular and blunt-edged, or are tabular. Feebly 

 translucent, or only translucent on the edges. Soft. 

 Intermediate between sectile and brittle. Easily fran- 

 gible. Feels rather greasy. Specific gravity, 2.6*7, 



Kirwan 2.474, Blumenbach 2.6300, La Methiie 



2.611, Breithaupt. 



Chemical Characters. It effervesces very violently 

 with acids : but is infusible before the blowpipe. 

 Constituent Parts. 



From Bremsgriin. 



Lime, . 55.00 



Carbonic Acid, 4-1.66 



Oxide of Manganese, 3.00 



From Kongsberg. 

 Lime, 56 00 



Carbonic Acid, 3<) 33 

 Silica, . 1.66 

 Oxide of Iron, 1 .00 

 Water, . 2.00 



Suersee. 



Gcognostic Situation. It occurs in primitive lime- 

 stone, along with calcareous spar, brown-spar, fluor- 

 spar, and galena ; in metalliferous beds, associated with 

 magnetic ironstone, galena, and blende ; and in veins, 

 along with tinstone. 



Gn. graphic Situation. Ft occurs imbedded in mar- 

 ble in Glen Tilt, Perthshire ; and in Assynt in Suther- 

 land : in Cornwall ; and near Granard in Ireland. On 

 the Continent, it is found along with tinstone, in the 

 Saxon Erzgebirge ; along with octahedrite, in a vein at 

 St. Chirstophe in Dauphiny ; also in Norway, in metal- 

 liferous beds, and in limestone. 



NINTH SUBSPECIES. 



AFHBITE, Jameson Schaumerde, Werner. 



This subspecies is divided into three kinds, viz. Scaly 

 Aphrite, Slaty Aphrite, and Sparry Aphrite. 



First Kind. 



SCALY APHRITE, Jameson. Schaumerde, Werner. 

 Zerreiblicher Aphrit. Knrslen. 



External Characters. Colours snow, yellowish, and 

 reddish white, sometimes passing into silver-white. 

 Occurs either friable or compact. Friable varieties 

 composed of glistening or glimmering particles, in 

 which the lustre is pearly. Particles are fine scaly, feel 

 fine, but not greasy. Either loose, or loosely cohering. 

 Compact varieties massive, disseminated, or in granu- 

 lar concretions, with a shining or nearly splendent 

 lustre, which is pearly, sometimes inclining to semi me- 

 tallic. Fragments indeterminate angular, and blunt- 



* The term tuft appears to be dervid from the verb TU$*, which, in its original signification, is appropriate to volcanic productions, 

 especially to such as are of a spongy or porous texture. Kid. 



5 



