ORDER II. AXOTOMOUS LEAD-BAKYTE. 149 



with various other species of the genus Lead-baryte. It 

 had been first noticed and described by Count BOURNOH, 

 as a variety of di-prismatic Lead-baryte. 



ii. Cupreous Sulphato-Carbonate of Lead. 



BROOKE. Edin. Phil. Journ. VoL III. p. 117. PHJLL. 

 p. 342. 



Prismatic. General form of crystals, a broad rectangu- 

 lar four-sided prism, Sim. Fig. 25., terminated by a hori- 

 zontal prism Pr (i), of 95, set upon the broad faces. There 

 occurs also a horizontal prism in the direction of the other 

 diagonal, of 143 42', and a vertical one, of 109, inclined 

 to the broad face T at an angle of 144 3(X, according to 

 Mr BROOKE, and various faces of scalene pyramids having 

 one of their edges situated like the horizontal prism of 95. 

 Cleavage parallel to this same prism i, also to the faces T 

 and 3/, indistinct. Fracture uneven. Surface streaked, 

 the vertical prisms parallel to their own intersections, the 

 inclined faces parallel to the intersections with Pr. Lustre 

 resinous. Colour deep verdigris-green ; inclining to moun- 

 tain-green, if the crystals be very delicate. Streak green- 

 ish-white. Translucent. Rather brittle. Hardness =2-5... 

 3*0. Sp. Gr. = 6-4, about, BROOKE. 



Mr BROOKE found it to consist of 55-8 of sulphate, 32-8 

 of carbonate of lead, and 11-4 of carbonate of copper. It 

 occurs at Leadhills, along with the preceding species. It 

 was first described by Mr SOWERBY as green carbonate of 

 copper. 



iii. Cupreous Sulphate of Lead. 

 BROOKE, Ann. of PhiL IV. p. 117- PHILL. p. 347. 

 Hemi-prismatic. A combination is described by Mr 

 BBOOKE,consistingofP--c(Jlf). ^L r 



Pr (J) = 61 (X ; Pr + CD and Pr + CD (P). The angle of in. 

 clination of P oo upon Pr + co is = 95 45'. The incli- 



