UNRECOKDKD AND OTHER MINERALS 



20 Deweylite. — {Hydrous basic iiiagnesiuni silicate.) 

 In thin seams, sometimes reaching a foot in width, 



traversing serpentine. Harman's Rivulet, near 

 the Parson's Hood Mountain. 



21 Dolomite. — {Carbonate of calcium and magnesium) 



Analysis of the pure white form from the Magnet 

 Mine. (F. O. Hill.) 



Ca 31 "72 per cent. = Ca Co 3 56*64 per cent. 

 Mg O 15-60 „ = Mg C03 32-76 

 Fe 3-92 ,. = Fe Co, 8*26 



Mn 1-80 „ = Mn C03 3-76 



101-42 



22 DuNDASiTE. — {Hydrous carbonate of lead and alu- 

 minium.) 



" Minerals of Tasmania," 1896, page 33. 



Dana, " First Appendix to the Sixth Edition of the 



System of Mineralogy," page 23. 

 The following is a complete analysis of this new 



species : — 



Pb = 38-84 per cent = Pb O 41-86 



AU O3 26-06 



Fe = 3-85 „ = Fe', O3 5-50 



H/O ■+ Co^ 28-08 



101-50 



Mr. Pascoe states that the Fcg and O3, or a portion 

 thereof, may be foreign to the substance, as it is 

 next to impossible to perfectly separate it, since it 

 almost invariably occurs as an incrustation on the 

 mineral from the original locality at Dundas. A 

 trace of P 3 O 3 was also found ; this was certainly 

 obtained from an extremely thin coating or skin 

 of pyromorphite, which is often present, and gives 

 an external green colouration to the surface of the 

 mineral. At the Hercules Mine, Mt. Read, a 

 mass of snow-white cellular quartz has been 

 obtained, throughout which are scattered crystals 

 of cerussite, gibbsite, and numerous patches of 

 dundasite, the whole forming one of the most 

 attractive associations of minerals as yet obtained 

 in this State. 



