Mr Solly , Liveingite, a new mineral from the Binnenthal. 239 
Liveingite, a new mineral from the Binnenthal. By R. H. 
Solly, M.A., Downing College, with analysis by H. Jackson, M.A., 
Downing College. 
\Abstract , read 6 May 1901.] 
This new mineral, to which I have given the name “Liveingite” 
in honour of the Professor of Chemistry, G. D. Liveing, F.R.S., is 
a new member of the group of sulpharsenites of lead which com- 
prise Sartorite PbS + As 2 S 3 , Rathite SPbS 4- 2As 2 S 3 , Dufrenoysite 
2PbS + As 2 S 3 and Jordanite 4PbS 4- As 2 S 3 . 
It crystallizes in the oblique system with a pseudo-rhombic 
habit, ft = 89° 45 J'. 
The crystals consist of a twin aggregation, twinned about 
( 100 ). 
The twinning is beautifully shown by the iridescent tarnish 
they exhibit ; one crystal has a green shade of colour, the other a 
red. 
This difference in colour of two similar twinned crystals is well 
shown in Jordanite. 
Through the kindness of Professor Liveing I have lately been 
able to make a few experiments on the artificial tarnishing of 
twinned crystals. The experiments made on Bournonite and 
Redruthite confirm the arrangement of tarnish observed in Live- 
ingite and Jordanite. 
The crystal habit is partially like Rathite and Sartorite. 
The development of the dome zone resembles Rathite, while 
in the prism it resembles Sartorite. The pyramid zone has planes 
not found on either Rathite or Sartorite. 
The prism zone exhibits oblique symmetry. I had only two 
crystals and the greater portion has been used by Mr Jackson in 
his analysis. 
I am hoping to obtain this summer more material so as to be 
able to fully describe the crystallographic characters of this new 
mineral. 
R. H. S. 
