. PROFESSOR HEDDLE ON THE MINERALOGY OF SCOTLAND. 221 


The Pink. ' The Blue, 
SiGe « i . 2° 543 S. G. ‘ : . 2°545 
On 1°3 grammes— On 1° 304 grammes— 
Silica, . 5 : 841 Silica, . ; ; 84 
From Alumina, . * 004 From Alumina, , - 007 
845 * 847 
Silica, : ang” : , : , 64°187 
Parminageme Wee ew 08S) Os Os) Sug fe S898 
Ferric Oxide, .. 1: 428 , : : me 0s 
Manganous Oxide, 692 ‘ : ; ; ; ‘461 
Lime, ; : 732 ‘ ‘ ; ; : ‘687 
Potash, : : 13 * 823 ‘ ; : d pm aie lal 
Soda, . , ; 1:003 ‘ A 4 é «ele 96 
Lithia, A : tr, : : ; < ; an 
Water, : ; - 501 : F A : : * 557 
100-211 99 -'750 
Loss in Bath, . RLOf pie, : ‘ ; -158 p.c. 
Insoluble Silica, . L*656p.c. - : : : aoe pic: 
Possibly the manganese is the cause of the colour of the pink: candour 
compels the confession that the chemistry of the present day fails in the 
detection of the colouring ingredients of the felspars. In the greater number of 
my analyses of orthoclase the state of the oxidation of the iron was determined, 
and, as it invariably proved to exist as ferric oxide, it was also set down as such 
in the few in which no special examination was made. 
From primitive Limestone,—“ Necronite.” 
15. The specimen examined was from a mass which lay between granular 
limestone and its associated augitic belt, on the hill slope above the farm-town 
of Balvraid, Glen Beg, Glenelg. 
Besides limestone, the mass contained Biotite, a hydrated labradorite of a 
fibrous structure, and a new mineral species—to be called Balvraidite. 
The orthoclase was very peculiar—it was considered oligoclase. Its colour 
was dove-blue, its lustre somewhat. pearly; -it was in cleavable masses ; its 
S. G. 2° 558. 
VOL. XXVIII. PART I, 3M 
