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NOTE ON SPODUMENE FEOM NAMAQUALAND. 
By G. C. Scully, M.A., and A. E. E. Walker, A. E.G. Sc., B.Sc. 
(Eeceived and Eead August 20, 1913,) 
The chief object of this note is to record the occurrence in Namaqua- 
land of a Hthia-bearing mineral whose optical and other physical properties 
enable us with considerable confidence to refer to the species Siwdumene. 
Spodw7iene is a lithium aluminium silicate whose chemical formula is 
given as Li^O . AI2O3 . 4Si02. 
This note is intended to serve as an introduction to a later paper in 
which we hope to supplement the description here given and also to deal 
with several of the other minerals which we have found in association 
with it. 
We collected the material described below in a prospecting pit near 
Jackals Water, about twenty-seven miles distant, in a northerly direction, 
from Steinkopf. 
It occurs in extremely coarse pegmatite (intrusive in gneiss) chiefly in 
the form of large prismatic crystals, many of which are from 3' to i' in 
length and from 6" to 1' in width ; also as veins. At, and near the surface, 
it is much altered to a white powder. 
The principal minerals of the pegmatite are milky quartz, microcline 
and muscovite mica, but, in addition to these — and closely associated with 
the Spodumene — there are greyish and somewhat smoky quartz (fre- 
quently graphitically intergrown with felspar), lithia mica, petalite (?), 
tantalite, and a pale brown garnet. Bismuth ochre is disseminated 
throughout. 
Three differently coloured varieties of Spodumene occur, viz., greyish 
white, pale amethyst, and pale green ; beyond these differences in colour 
there are no noticeable variations either in physical or chemical properties. 
All three possess a degree of hardness equal to that of quartz. 
The results of a large number of determinations of the specific gravity 
vary from 3-16 to 3*18, these variations being attributed to slight differences 
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