Heavy Spar. 5^3 Eafily frangible. Heavy. Gcognostic and Geographic Situations. It is found in beds along with galena, at Peggau *n Stiria ; alfo in the mining field of Freyberg, and at Schlangenberg in Siberia, where it is accompanied "nth copper green and native copper. Obfcrvalions. i. It bears a ftriking refembtance to granular Kmeftone, from which, however, it is dtftmguifhed by the following characters : 1. It has lei's lull re 2. When the diftinCt concretions are of the fame fize as in granular limeftone, they are , not fo well defined. 3. It is fofter, and 4. It is much heavier. a. The greater or lei's Angular diftinanefs of the concretions, affords, to an experienced eye, a good m ark by which to diftinguifh granular limeftone, granular heavy fpar, and granular gyps from one a nother ; thus in granular limeftone they are wo ^fined, in granular heavy fpar kls an( * m & ra °nlar gyps {till more indiftinfr-