390 



THE GEOLOGIST. 



2. Qnartz, Hornstone, Brown-spar, Calc-spar, and Spatliic-iron are 

 combined witli Argentiferons galena, Blende, Arsenical pyrites, 

 Argentiferous pyrites, and Copper-pyiites in moderate quantities. 

 More rarely, and particularly in druses, tliere are found Chlorite, 

 Baryte, Fluor-spar, Falilerz, Rotligiltigerz, &c. : red-iron is found as 

 a so-called eiserner Hut" or "gozzan" to tlie foregoing. This com- 

 bination has been named the "Lead-pyrites formation," and pre- 

 dominates east and south of Freiberg. About three hundred veins 

 have been found belonging to it, and their direction is mostly forty- 

 five degrees east of north. This combination is intimately connected 

 with the following — 



3. Brown-spar, Manganese-spar, and Quartz, with Calc-spar, Ba- 

 ryte, Spathic-iron, Argentiferous galena. Argentiferous blende. 

 Argentiferous pyiites, Arsenical pyrites, Bothgiltigerz, native Silver, 

 Federerz, &c., often forming symmetrical layers in definite succes- 

 sion. Bed Iron occurs as a gozzan. Over three hundred veins, 

 mostly bearing forty-five degrees east of north, or north and south, 

 belong to this " gTeat Lead-formation," which, like the foregoing, is 

 more particularly developed east and south of Freiberg. 



4. Baryte and Fluor-spar predominate, and alternate with Gralena 

 in many thin and regular layers. With these are associated, 

 particularly in the druses in the middle of the vein. Quartz, 

 Spathic-iron, Calc-spar, Brown-spar, Iron-pyrites, brown Blende, 

 richly Argentiferous fahlerz. Copper-pyrites, Rothgiltigerz, native 

 Arsenic, Bauschgelb, Grrauspiessglaserz, native Silver, Glaserz, 

 &c. The veins of this " Barytes-lead formation," which mostly 

 bear forty-five degrees east of south, predominate in the neigh- 

 bom^hood of Halsbriicke. We have counted about one hundred 

 and thu'ty. 



These fom' combinations or formations may, perhaps, in considera- 

 tion of the gTeat similarity of the 2nd and 3rd, be reduced to three, 

 of which the most general characteristics are as follows : — 



I. Quartz and Hornstone, Avith many fragments of neighbouring 

 rock and with noble ores, particularly in druses. It predominates 

 north and west of Freiberg. 



II. Quartz and Carbonates vdth. Sulphides of metals, partly 

 massive, partly disposed in layers. Predominates east of Freiberg. 



