1821 1 Mr* Weaver on Floetz Formations. 343 



more rarely and single teeth occasionally; fragments of zoo- 

 hvtes near Schmerbach in Gotha; trilobites, designated by 

 phytes, near oe , trilobites bituminosus, in the copper 



Baron von ScWoAemi as tnlo of Riege lsdorf ; shells 



Rarely buttiall' g^phites,* telhmtes, striated terebratu 

 htel amlnites, and belemnites, have been observed, beside 



*«5*f ££££•— * more scarce in the copper shale, 

 and les * determinate ; such as impressions resembling lycopodia 

 ferns , leaves! ears of 'corn, the jo'inted stem of the bamboo, and 



Se ThTrl e of' shale, or grey marl shale : appears sometimes cor- 

 roded or vesicular, resenibling scoria, the cavities being empty, 

 or coated with a calcareous sediment, or encrusted with crys- 

 tals of carbonate of lime. In some quarters it contains fine 

 la dy layers! resembling rauhstein ; in others, it approaches to 

 he characte of slaty swinestone, and m others to that of bitu- 

 minous marl shale. Occasionally it contains also copper shale 

 mthinsteeaks; fibrous gypsum, and calcareous .spar payers 

 strings and disseminated portions ; iron pyrites in thin lay ei, 

 and strings- and copper ores, disseminated for short distances. 

 The oniforganic remains found in the roof shale are gryphites, 

 rprpntlv met with near Hettstadt. . 



Zechsteln.-A compact limestone, commonly thinly stratified, 

 and mo e or less argillaceous, containing in Mansfeld about one- 

 sixth part of alumine, and in Lower Saxony one-fourth : extremely 

 tenacfous, whence its name of toughstone ; usually ££. *J* 

 sometimes approaching to black ; and occasionally vesicular the 

 cavities being coated with a ferruginous deposit. In general 

 external character, it much resembles that compact variety ^o 

 shell limestone, which has a splintery, even ™^™ c ^ d £ 

 fracture + It varies in thickness from 14 to 112 teet, ana in 

 X^itere forms abrupt rocky hills ; the «be«, 

 times curiously inflected; but in some parts of the tores , ot 

 Thuringia, it is wanting altogether, the ferriferous or gryphite 

 limestone appearing in its stead. . , 



Occasional intermixed minerals : calcareous spar m ^ttered 

 folia in strings, and lining drusy cavities, and fibrous carbonate 

 of 1 me in layers two or three inches thick ; gypawn, compact, 

 granular, and specular, in nodules, or disseminated d oj 

 lypsum in layers and strings ; clay galls rarely; quaitz crystals 

 with brown iron ochre, in nests and streaks ; and in the lower 

 strata, particles of mica. . „ rQ ^ r i Q. 



Metallic substances : brown iron ore m thin layers or gaodes , 

 clay ironstone, and black clay with disseminated ire* ipyntes, m 

 nodules ; and some copper ores, in disse m mated £»■» 

 Lower Saxony, also, galena, in nests and strings, bes.de traces 

 of mineral pitch. 



• Gryphite* aculeatu*. (See Petrefactenku.uk of Baron von Scldotheim.) 

 -f- Lias limestone. 



