I. On the Sodalite at Salem, Mass. 

 BY D. M. BALCH. 



(Communicated February 8, 1864.) 



The occurrence in our neighbourhood of this rare silicate was 

 first noticed in Oct. 1855, by G. L. Streeter Esq., and others. 

 The locality was the recently opened syenite quarry, on the 

 right hand side of the road leading along Collins' Cove, from 

 the Alms House to Hospital Point Peculiar bluish stains in 

 a block of stone from the quarry having attracted the attention 

 of these gentlemen, a search was instituted which resulted in 

 the discovery of the remains of a vein of elseolite and orthoclase, 

 in which were imbedded jimorphous masses of the blue mineral, 

 sodalite. Unfortunately this vein, once extensive, had been 

 mostly quarried and carted away by the workmen, and, though 

 it yielded some fine specimens, was soon exhausted. 



An account of the discovery of this mineral and some discus- 

 sion thereon (in which it is erroneously called cancrinite, ) can 

 be found in the Essex Institute Proceedings, Vol. I, p. 153 

 155; also a more extended description and analysis, by J. P. 

 Kimball in Silliman's Journal; 1860, Vol. xxix. p. 65. 



I visited the above locality in the autumn of 1858, and traced 

 the vein some distance, until it was reduced to a mere seam ; I 

 noticed at that time several characteristics, rendering it highly 

 improbable that the Salem mineral had a common origin with 

 that of Lite h field, Me., its only other locality in the States. 

 At the place last mentioned sodalite occurred disseminated 

 through an erratic block, and associated with elasolite, citron- 

 yellow cancrinite, and zircons of unusual size and excellence 

 (all long since exhausted .) while at the Salem locality it was 

 found imbedded in a vein of elaeolite and feldspar, with very 

 small zircons, biotite, marcasite, plumbago, &c.; but no trace 

 of cancrinite, the most conspicuous of all in the Maine group. 



