Tourmaline of gem quality has recently been discovered in the Hundred of Dudley, Kangaroo Island, South Australia. Mr. H. Y. L. Brown, Government Geologist, South Australia, savs' :-" The stones are remarkable for their size and e~l1ty, and after passing through the lapidary's hands form very handsome gems. The prevailing color is green in varions shades, although some of the crystals have centres of a delicate pink calor. Sales made show that the stones have commercial
value in the rough, aud the discovery bids fair to be of importance." By the kindness of Mr. E. F. Pittman, Under-Secretary for Mines and Agricnlture, New South Wales, and the good offices
of Mr. G. W. Card, Curator and Mineralogist to the Geological Survey, I have been enabled to examine and measure some crystals of tourmaline from this locality on view in the Mining
and Geological Museum, Sydney. The six crystals examined in detail had been attached by one
end, consequently show only one termination. Apparently they are of the usual columnar habit. The colour varies from practically opaque black at the apex, to transparent green towards the
broken end, but there is no definite line of demarcation in the tint afl is sometimes obRerved in tourmaline. lo The faces in the prismatic zone are as usual rounded and striated, amI in the figured specimens only the forms which were definitely recognised are taken account of. The commonest termination is evidently a combination of rand 0 simply, 0 predominating.
Orystal I.-(PI. xl., fig. 3.).-It measures 7 mm. x 3 mm. Only one prism was clearly identified, namely the diagonal prism a (1l~0). The crystal is terminated by r (1011) and 0 (0221). The latter in large, roughly triangular faces predominates, r being represented by narrow planes. All the forms are
present in the full complement of faces..... article date de décembre 1904 http://australianmuseum.net.au/uploads/journals/16869/1069_complete.pdf
value in the rough, aud the discovery bids fair to be of importance." By the kindness of Mr. E. F. Pittman, Under-Secretary for Mines and Agricnlture, New South Wales, and the good offices
of Mr. G. W. Card, Curator and Mineralogist to the Geological Survey, I have been enabled to examine and measure some crystals of tourmaline from this locality on view in the Mining
and Geological Museum, Sydney. The six crystals examined in detail had been attached by one
end, consequently show only one termination. Apparently they are of the usual columnar habit. The colour varies from practically opaque black at the apex, to transparent green towards the
broken end, but there is no definite line of demarcation in the tint afl is sometimes obRerved in tourmaline. lo The faces in the prismatic zone are as usual rounded and striated, amI in the figured specimens only the forms which were definitely recognised are taken account of. The commonest termination is evidently a combination of rand 0 simply, 0 predominating.
Orystal I.-(PI. xl., fig. 3.).-It measures 7 mm. x 3 mm. Only one prism was clearly identified, namely the diagonal prism a (1l~0). The crystal is terminated by r (1011) and 0 (0221). The latter in large, roughly triangular faces predominates, r being represented by narrow planes. All the forms are
present in the full complement of faces..... article date de décembre 1904 http://australianmuseum.net.au/uploads/journals/16869/1069_complete.pdf
