202 



RECORDS OF THE AUSTRALIAN MUSEUM. 



ANGLESITE. 



Dnndas, Tasmania. 



(PI. xxxviii., figs. 2, 3, PI. xxxix., figs. 2-6.) 



At the Dundas miues anglesite is a characteristic mineral occurring 

 in well developed crystals, which are sometimes of large size. In a 

 previous paper ^ a crystal from the old Maestries Mine was described and 

 figured, and the occurrence of the mineral has been referred to by the 

 late W. F. Petterd.'^ 



A hand specimen was recently presented hj Mr. E. Hull. It is not 

 known from what mine the specimen came, but, as it carries crystals of a 

 habit unusual for the Dundas anglesite, some of them were measured and 

 one is figured (PI. xxxix., figs. 2, 3). The crystals are transparent and 

 glassy, and occur in vughs in a matrix of galena ; a few crystals of 

 cerussite are also present. The anglesite is tabular in habit and elongated 

 parallel to the b axis, the largest crystals being about ten mm. long ; 

 only VI (110) is present in the prism zone, and no brachj'-domes are 

 developed, the largest faces being r (001) and / (104). 



Four exceptionally fine specimens of anglesite from the Comet Mine, 

 Dundas, were recently added to the collection. One of these consists of a 

 mass of beautifully developed, clear, colourless crystals of modei'ate size, 

 accompanied by limonite. The limonite was formed prior to the anglesite, 

 and is stalactitic, the anglesite being deposited round tlie stalactites ; the 

 limonite when fiesh is seen to have a radiated structure, but as a I'esult 

 of decomposition it has been largely converted into a yellow powder or 

 completely removed, leaving a series of parallel tubes penetrating the 

 anglesite. 



The crystals were found to be exceptionally rich in faces, a total of 

 fifteen forms, one of which is new, being established. Tlie combinations 

 observed on six crystals are tabulated below. 



1 Anderson — Rec. Austr. Mus., vi., 1905, pp. 90-91, pi. xix., tig. 3. 



2 Petteid— Papers and Procs. Roy. Soc Tas., 1900-1 (1902), p. 83; Cat. Mins. 

 Tas., pp. 8-9 (Ilobart, Govt. Prmter, 1901). 



