The Mineral Resources of Greenland. 4] 
Graphite as a constituent of Tertiary basalt or of anorthite 
nodules therein. 
Graphite is a comparatively common and characteristic accessory 
mineral in both the native iron-bearing and the ordinary Tertiary 
(Miocene) basalts and andesites of Disco Island and Nugsuak Peninsula. 
К. J. У. STEENSTRUP indeed reports that graphite is never absent from 
the native iron-bearing rocks, and so constant is the association of 
native iron and graphite that there may well be a genetic relationship 
between the two. Graphite at Ovifak not only occurs according to 
TscHERMAK in the anorthite nodules of the iron-bearing basalt, but also 
as black, finely-disse- 
minated particles in its 
groundmass. Analyses of 
this basalt show from 
0.3 to 3.52% of carbon. 
LAON ANR | 
NicoLAu reports numer- ===; re RZ. 
ous plates of graphite DR RS ee Se 
с © Е ata food no oo NEBr SP ae 3.090 TOTS TCS 
inthe plagioclase pheno- SS Se ee ae 
2.909.805 aaa KER + = 
crysts of the Jernpyn- SR ee 
ten andesite. === % 
In the native iron- = Ses 
bearing basalts and Fig. 16. Graphite in basalt dike Upernivik Island, 
andesites are segrega- after K.J.V.Steenstrup Medd.om GrönlandIV Pg.130. 
tions of tabular anor- 1. Shale Cretaceous sediments. 2. Sandstone Cretaceous sediments. * 
thite crystals, from the 3. Columnar basalt. 4. Normal basalt. 5. Graphite in basalt. 
size of а hazel nut to 
that of a walnut. They are so richly flecked with graphite dust and scales 
as to resemble lumps of graphite. These contain up to 6.78 % of carbon. 
K. J. V. STEENSTRUP!) found graphite at several localities in basalts 
which contain no native-iron. At Kook angnertunek (south coast of 
Upernivik Island (Umanak Fiord) is a basalt dike intrusive in Cretaceous 
sandstone and shale (see Fig. 16) which near its borders has a columnar 
structure. In one part of the dike graphite occurs in rounded lumps 
as large as peas. Small balls of graphite are also reported by K. J. V. 
STEENSTRUP in basalt from Nuk. 
The graphite may represent as claimed by many geologists carbon- 
aceous matter derived from the Cretaceous and Tertiary sedimentary 
beds traversed by the flow rocks before reaching the surface, but I 
am inclined to believe it a part of the original magma. Graphite is 
not only a constituent of meteorites but, in instances, of igneous rocks 
notably kimberlite, where it occurs in both nodules and the main rock 
1) Meddelelser om Gronland, 4, 1883 р. 130. 
