NESCUTE OM 0) fia Lolle 
FENG pA 
78 > Pentti Eskola. (LIE 
VII. Melanite-syenite, North end of Cnoc-na-Sroine, 
Scotland. Analyst A. Gemmell, »Chemical Analyses of Boro- 
lanite and related Rocks», Transact. Edinburgh Geol. Soc- 
IX, p. 418 (1910). 
VIII. Assyntite, 1; mile east of Ledbeg, near Cnoc-na- 
Sroine, Scotland, A. Gemmell. loc. cit. p. 418. | 
IX. Ledmorite, Ledmore River, near Cnoc-na-Sroine, 
Scotland. Analyst A. Gemmell, ibid. p. 419. 
X. Borolanite, Am Meallan, near Cnoc-na-Sroine, Scot- 
land. Analyst W. Campbell Smith, »On the Conn of 
Borolanite», Geol. Mag. vol. VI (1909). 
XI. Leucite-tephrite, Toscanella, Lake Bolsena, EKA 
Analyst H. S. Washington, Roman SP Region. 
Carn. Inst. Publ. 57, 1906. 
The characteristic features of each of these rocks are 
fairly apparent from the calculated n or ms and these are - 
therefore quoted in another table. 
The feature which no doubt first attracts attention in 
the sviatonossites is their high percentages of lime as well 
as of alkalies. In this respect they are like the monzonites 
(analyses III and IV), though the ålkali oxides in the latter 
hardly ever attain as high percentages as in the rocks in 
question. A difference apparent at first sight from the per- 
centage figures is the higher quantity of MgO0 and FeO in 
the monzonites. The percentages of CaO are approximately - 
equal in both rocks, and the percentages of alumina also 
do not show any general difference. The somewhat lower 
quantity of the alkalies present in the monzonites makes, 
however, a large part of lime enter into the plagioclase 
and consequently the percentage of the anorthite is higher. 
The amount of (Fe, Mg)O being also higher there appears 
hypersthene or olivine in the norm besides much diopside. 
In the sviatonossites, on the other hand, lime is in excess 
over magnesia and ferrous oxides as well as over alumina: ' 
therefore the norm shows little anorthite and no hypersthene 
or olivine, but instead of these much wollastonite — a nor- 
mative mineral which only rarely enters into the norms of 
gineous rocks. 
fs GES ; 
PRAT NR 
ME 
3 q [4 - k NÅ 
LA > 2 å q RR rd 
ÅA ÄR snett AR nn nn nn Nn an GO AL lg 
a ; > > 4 fa - 4 "i nd 
IRENE PRAT VA SU 
