196 BASALT. 



Jonzac, France. 



The Joiizac meteorite is stated by Tscherniak to have a fragmental strnctuve, and 

 under the microscope is seen to be composed of lamelloe of anorthite and columns of 

 augite. The former has distinct bounding lines, while those of the augite are indistinct. 

 Lying between these crystals are small grains of the same minerals, filling the interspaces. 

 The anorthite is often cloudy from minute brown glass inclusions, and black grains arran- 

 ged parallel to the length of the crystal. The augite when clear has a greenish-brown 

 color, but it is often traversed b^^ fissures, and rich in violet-blue, and brown, dust-like 

 particles, — chromite and pyrrhotite, possibly. The meteorite further contains pyrrhotite, 

 chromite, and iron.* 



Petersburg, Lincoln Co., Tennessee. 



The Petersburg meteorite is, according to Professor Shepard, of an " ash-gray color, with 

 a slight intermixture of pearl-gray, for the basis of the stone." Porphyritically inclosed 

 in this grouudinass are crystals and grains, which, from Shepard's and Smith's descrip- 

 tions, appear to be augite, plagioclase, and olivine. Some chromite and a garnet were 

 reported.! 



Tscherniak states that it is composed of anorthite, augite, and a yellowish silicate like 

 olivine.^ 



The specimen in the Harvard College Cabinet macroscopically closely resembles the 

 Stannern meteorite. 



FranJifort, FranJdin Co., Alabama. 



The Frankfort meteoric stone, according to Professor Brush, presented a gray ground- 

 mass with a pseudo-porphyritic structure, having black, green, white, and dark-gray spots 

 on it. Professor Brush determined the minerals as follows : the black one as chromite ; 

 the white as anorthite or chladnite (it is more probably feldspar than enstatite) ; the 

 green and gray as olivine (probably some augite also) ; and, in addition, a little nickel- 

 iferous iron, and pyrrhotite (troilite). This rock seems to be a basalt, to which its chemical 

 analysis refers it.§ 



Variety. — Gabbro. 



LuotolaJcs, Finland, Russia. 



The meteorite from Luotolaks was found by Professor F. J. Wiik to be composed of 

 metallic iron; colorless anorthite; grayish-violet augite, inclosing long black microlites ; and 

 olivine, with little irregular cavities. || He refers this meteorite to the basic eruptives. 



Tschermak describes it as a tufaceous mass, which, in an earthy, friable, gray ground- 

 mass, holds splinters and grains of greenish, whitish, and dark color, as well as basaltic 

 (eucritic) fragments. He looks upon it as a volcanic ash. It contains, according to him, 

 anorthite holding little rounded glass inclusions ; augite in brownish grains, with black 

 needle-formed inclusions ; bronzite in very pale, greenish splinters, almost free from 

 inclusions; olivine, chromite, pyrrhotite, and iron. ^ 



* Mill. Mitth., 1874, pp. 168, 169. 



t Am. Jour. Sci., 1857 (2), xxiv. 134-137; Safford's Geo!. Ecconn. of Tcim., 1856, pp. 125-127; 

 Geol. of Tenn., 1869, pp. 520, 521. 



% Mill. Mitth., 1874, p. 170. § Am. Jour. Sci., 1S69 (2), xlviii. 240-244. 



II Neues Jahr. Min., 1883, i. 384; Ofvorsigt Fiiiska Vet. Soc. Forh., 1882, xxiv. 63, 64. 

 ^ Die niikros. Besch. der Meteoriteu, 1883, i. 7, S. 



