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GILLIGAN : THE LOWER PERMIAN AT ASHFIELD, ETC. 
Rutile. — Present in relatively small quantity, compared with 
garnet and zircon. Usually it occurs as prismatic needles, pyramidal 
faces being extremely rare, while rounded grains are common. The 
colour varies from deep yellow to brownish red. No case of twinning 
has been noted. 
Anatase. — Separate grains do not occur, but it is often associated 
with ilmenite and leucoxene. 
Xenotime. — The clouded and purple crystals similar in other 
respects to zircon have been referred to this mineral. 
Ilmenite. — This is a common constituent. Very frequently it is 
enveloped in the white alteration product leucoxene with outgrowths 
of anatase. It is more abundant than magnetite. 
Hematite. — Rounded grains of bright red colour by reflected light 
ociur plrnMfully. 
Liinonite. — This mineral is equally as abundant as hematite.^ 
Tourmaline. — The grains of this mineral are usually rounded, 
though a few stumpy crystals consisting of prisms terminated by 
simple rhombohedra occur. The colour is most frequently brown, 
having in one case a blue border. Only one graiji of distinctly blue 
tourmaline has been seen. The pleochroism of the brown variety is 
usually intense. Inclusions are somewhat rare. 
Apatite. — A few crystals of this mineral have been noted. 
Staurolite. — This mineral is of frequent occurrence. Usually it is 
quite fresh. The characteristic form is that bounded by cleavage 
faces, and presenting a " toothed " appearance. The colour varies 
from amber yellow to brown and the pheochroism is distinct. 
Biotite. — Both the brown and green (chromium) varieties (-ccur, 
though the latter is not abundant. 
Chlorite and Epidote. — These occur as rounded grains, very similar 
in colour, but the high birefringence of the latter and the low bire- 
fringence of the former enable them to be separately identified. Both 
are somewhat rare. 
Monazite. — Of this mineral, only one undoubted grain has been 
