BY W. F. PETTERD, CM.Z.S. 59 



ing mineral is known to occur. At the Adelaide Mine 

 green-stained dolomite also occurs in connection with the 

 lode, and has been plentifully produced in the ordinary 

 mining operations. It may be mentioned that chroraite 

 (Fe Cr2U4) occurs in moderate quantity throughout the 

 serpentine area of the Heazlewood district, but is not 

 known in the vicinity of the Magnet. 



The small doubly terminated crystals of crocoi.^ite from 

 the Magnet locality have been studied and described by 

 Dr. C. Anderson, M.A., B.Sc. (" Records of the Australian 

 Museum," Vol. VI., Part 3). He states: — "The matrix 

 is a rather friable limonite, in which the crocoisite is partly 

 embedded. The largest specimen carries numerous crystals 

 about 2 mm. in length ; in the other cases, where in situ, 

 the crystals are quite minute. . . . Qualitative analy- 

 sis proves their composition to be chromate of lead, and, 

 like the larger crystals, they agree morphologically with 

 crocoisite. The habit is remarkably constant throughout, 

 the crystals being prismatic by extension along the zone 

 axis ^)f. This zone, being the only well-developed one, 

 was made equatorial, and a stereogram constructed from 

 the co-ordinate angles obtained. From this the forms were 

 identified by means of Penfield's protractors, and the 

 identification was confirmed by calculation of the normal 

 angles. All the faces are small, with the exception of t 

 (111) which gives an excellent image and a peculiar 

 rounded face, which could not be determined, but is pos- 

 sibly X (301); the pinacoid b (010) is very small when 

 present." The Dundas crystals have been fully studied 

 and described by C. Palache (" American Journal of 

 Science," 1896, page 389), who states respecting the crystals 

 from the Adelaide Mine, Dundas : " The specimens were 

 implanted on limonite, and consisted of numerous crystals 

 clustered upon bases of lamellar gangue. The crystals are 

 of a light hyacinth-red colour, quite translucent, and with 

 adamantine lustre. They vary in size from minutest 

 needles to prisms of 2 cm. and 3 mm. diameter. The 

 habit is prismatic and the crystals are never doubly ter- 

 minated, being attached at one end to the limonite. The 

 larger crystals are often cavernous, giving rise to hollow 

 prismatic forms. As is usually the case with crocoisite, 

 the crystal planes are even and brilliant, giving good 

 reflections on the goniometer. The faces of the prism zone 

 are, however, strongly striated, parallel to the prism edges, 

 and this renders the identification of some forms doubt- 

 ful. Four crystals were subjected to measurement, and 



