,30 MINERALOGY. 



CALCAREOUS GRIT. 



There is a calcareous grit apparently of the tertiary 

 formation, found on the Tenasserim in about latitude 14° 

 20'. It is composed of grains of sand united by a calca- 

 reous cement. It is of a uniform grey color, and makes 

 the best whetstones that are found in the provinces. 



CHALK- 



Chalk is seen in the bazars, but it does not appear to be 

 a production of this country, being imported from Ben- 

 gal. 



cggo ojaojgi. c££8£o1- 



MAUL. 



The soil may be characterised as marly in the neigh- 

 borhood of some of the limestone ranges, but no beds of 

 marl have yet been discovered. 



CALCAREOUS TUFA. 



Several varieties of calcareous tufa are found in the 

 vicinity of the limestone rocks, formed by the deposition 

 of the waters that run over them. They often contain 

 shells belonging to existing species ; especially Helix 

 angu ina, and Cyclostoma tuba. 



A RR ACONITE. 



Some of the caves on the Sahven furnish a species of 

 double refractive spar, which I judge to be Arragonite. 



DOLOMITE, OR MAGNESIAN CARBONATE OF LIME. 



A few of the limestones in the east part of Amherst Pro- 

 vince, Mr. O'Riley found to be magnesian carbonates . 

 and Prof. Mitchell in his analysis of the lead ore from the 

 Salwen-limestone found m p gnesia among its consti- 

 tuents. 



A limestone in Arracan, Mr.Stilson has used as a litho- 

 graphic stone in a small way ; but it does not do well. 



