PROFESSOR HEDDLE ON THE MINERALOGY OF SCOTLAND. 479 
Specific gravity, 3° 3293. 
25 grains yielded— 
Silica “4... «a 8537046 
Alumina, . . ; Bi 7 Boros a} 
Ferrous Oxide, . : ao AE S89 
Manganous Oxide, . : 078 
Lime, ; : : < US) Se 
Magnesia, . : : leone 
Water, : é ; : -626 
101 +339 
Seemed pure. 
16. From Hart o’ Corry. From Principal Forses. In large green crystals, 
which weather pale, and assume on an outer film a lustre which is metallic 
and somewhat bronzy. Associated with magnetite, pale-green labradorite, 
anorthite (?), very little olivine, and traces of earthy chlorite, or a substance 
resembling it. 
Specific gravity, 3-329. 
1°505 grammes yielded— 
Silica, : ; : Seals 62 
Alumina, . : ! , IL COX 
Ferrous Oxide, . ; a e968 
Manganous Oxide, . *332 
Lime, ‘ : : ; 20837 
Maenesia; . 4 : . 16°471 
Water, : P : : BA: 
100:°172 
9-185 per cent. of the silica insoluble ; possible impurity, labradorite (?). 
17, From Drum na Raave (Rabm). Specimens from Mr Grieve. Slightly 
weathered, with a brownish-green colour, and a slightly bronzy lustre; no 
impurity visible to lens, but there were barely visible cavities which had held 
magnetite ; which therefore may be present in minute quantity in the centre of 
the mass. Was associated with pale-green translucent labradorite ; this, when 
in contact with the somewhat bronzy hypersthene, is usually of a grey colour. 
Specific gravity, taken on a very fine piece of 641° 15 grains, =3 : 335. 
The magnet extracted nothing from the crushed mineral. 
Cleavage a. perfect, splendent, and bronzy. 
b. flat and lustrous. 
M. interrupted and somewhat dull. 
Angles aon 6 90°. 
M onM 87° 22’ to 87° 05’;—87° 15’ common. 
