40 Elements of Mineralogy. 



5 of iron: the iron appears to be accidental, 

 and its quantity greater or fmaller, according 

 to the colour of the ftone. 



II. VARIETY. 

 Creutzenwald Stone. 



This ftone is mentioned, but not defcribed 

 by Mr. Bayen. 13 Rox. 59. It is probably 

 of a brown, or yellowifh colour, and great 

 weight; it contains by Mr. Bay ens account, 

 75 per cent, mild calcareous Earth, 1 2 mild 

 magnefia, and 13 of iron. It is found near 

 Creutzenivaldy and there ufed as a flux for 

 iron ores. 



SPECIES VI. 



Mild Calcareous Earth mixed *whh a notable 

 Proportion of Clay. 



I. VARIETY. 

 In a loofe Form. Calcareous Marl. 



Marl is well known from its life in. Agri- 

 culture. I diftinguifh two forts of it, the 

 calcareous and the argillaceous ; it is of va- 

 rious colours, grey, yellow, red, brown, or 

 bluifli ; thefe arife from a mixture either of 

 iron or pyrites. The calcareous ftrongly ef- 



fervefces 



