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PART II. 



STRATIGRAPHY 



MOLTEN o BEDS. 



The general features of the Molteno Beds are described by Rogers 

 and du Toit in "The Geology of Cape Colony" as follows: 



"The Molteno Beds are first met with at a point a little to the 

 east of Steynsburg and form the higher-lying ground in the Division 

 of Molteno; they extend along the fort of the Stormbergen into 

 Herschel, the Orange River Colony, and Basutoland, and along the 

 base of the Drakensbergen through East Griqualand into Natal. 



The formation consists of sandstones, shales and mudstones, the 

 softer beds being much like those of the Ecca and Beaufort, grey, 

 greenish or bluish in colour, but without the calcareous concretions 

 so abundant in the lower groups. 



Fossil plants are in places abundant, but seem if anything to be 

 more plentiful in the lower half of the Molteno Beds; silicified wood 

 is common in some of the sandstones. 



The sandstones of the Molteno beds are quite unlike any that 

 occur in the lower groups of the Karroo system. In general appea- 

 rance and in the character of the surface to which they give rise, 

 they resemble the Table Mountain Sandstone more closely than any 

 other in the Colony, but they are coarser in grain and much looser 

 in texture. In most localities the quartz grains are coated with a 

 later deposit of quartz with more or less perfect crystalline faces 

 which reflect light well, so that the rock sparkles in the sunlight. 

 To such varieties the term "glittering sandstone" has been appro- 

 priately given. 



Grains of felspar are abundant in these sandstones, sometimes in 

 such quantity that the rock can almost be termed an arkose. The 

 loose texture of the Molteno sandstone has allowed the felspar to 

 weather considerably, and the dull white grains of weathered fel- 

 spar are always conspicuous constituents of the sandstones, more 

 specially in the liner grained varieties. Rounded or spherical nodu- 



