360 



C. A. SUSSMILCH AND W. G. STONE. 



the hornblende and augite are remarkably fresh, considering 

 the amount of alteration which the felspar phenocrysts 

 and the groundmass have suffered. 



Iron ores. — These are very sparingly present, pyrites 

 being the most abundant ; a little magnetite is present. 



Groundmass. — This is much altered, and where it admits 

 of any examination it is seen to consist of a microcrystalline 

 to cryptocrystalline base of felted microlites of felspar 

 with some ferro-magnesian mineral, probably augite. A few 

 small patches of calcite were noted. 



Chemical Composition (x 63). 



Per cent. 



Si0 2 



50-05 



A1 2 3 



19-56 



Fe 2 3 



0-90 



FeO 



6-48 



MgO 



6-30 



CaO 



5-20 



Na 2 



2-49 



K 2 



3-09 



H 2 (100° C.) 



0-43 



H 2 O(100°C.+ 



) 3-90 



co 3 



0-32 



Ti0 2 



0-55 



Zr0 2 



absent 



P 2 5 



0-38 



so 3 



0-03 





Per cent. 



Orthoclase . . . 



18-35 



Albite 



20-96 



Anorthite 



23-63 



Corundum 



3-47 



Hypersthene... 



24-00 



Olivine 



1-45 





Per cent. 



CI 



trace* 



S(FeS 2 ) 



trace* 



Cr 2 3 



absent 



NiO and CoO 



trace* 



MnO 



0-09 



BaO 



0-15 



SrO 



f trace 



Li 2 



absent 



v 2 o 3 



0-05 





99-97 



Specific gravity 2-775 

 * Trace less than 0-01%. 

 f Spectroscopic reaction only. 



Nort 



Magnetite 

 llmenite 

 Apatite 

 ELO, COo 



etc. 



Per cent. 



1-39 

 1-06 

 1-01 

 4-65 



99-97 



Class II. Dosalane. 

 Order 5. Germanare. 



Rang 3 Andase. 

 Sub-rang Shoshonose. 



Magmatic name Shoshonose. 



