470 LIST OF MINERALS, THEIR 



HUMITE. A right rhombic prism ; M on M', 120. 



Hyacinth, a name sometimes applied to a red variety of 

 Zircon, and sometimes to Cinnamon-stone. 



Hyalite, see Quartz. 



Hydrargillite, see Alumine, phosphate. 



Hydrophane, see Quartz, opal. 



Hydropite, see Manganese, silicate. 



HYPERSTENE, blue from Greenland, see Amphibole. 



from Labrador; Paulite. Cleavage parallel to the 

 planes, and to both the diagonals of a rhombic prism^ 

 of 93 30 7 . The bright plane which is apparent in 

 the specimens of this substance, is parallel to the 

 short diagonal of the prism. There is no cleavage 

 that I can perceive transverse to the axis of the prism, 

 but I have a fragment of a crystal which indicates an 

 oblique termination inclining upon the acute edge of 

 the prism. 



The Bronzite and Schiller spar have cleavages 

 similar to the Hyperstene, and measure very nearly 

 the same ; but the Bronzite is much softer than the 

 Hyperstene, and the Schiller spar softer than the 

 Bronzite, and are probably therefore distinct minerals. 



IJ 



JADE. Axe-stone. Beilstein. 



Nephrite. Ceraunite. 

 Jargon, see Zircon. 

 Jasper, see Quartz. 

 ICE-SPAR. A right oblique -angled prism', MonM', 129 40', 



as measured by W. P. 

 Ichthyopthalmite, see Apophyllite. 

 IDOCRASE ; Egeran ; Vesuvian ; Wiluite. 



crystallised. A right square prism; P on a plane 



belonging to mod. class a, 142 50'. 

 red, containing Magnesia ; Frugardite. 

 greenish yellow, containing Manganese ; Loboite. 

 amorphous. 

 JEFFEUSONITE. 



crystallised. The crystals resemble one of the opaque 

 varieties of Pyroxene. The cleavages are parallel 

 to the terminal and lateral planes, and to both the 

 diagonals of an oblique rhombic prism^ of about 

 87 and 93, oblique from an acute edge. These 

 angles are nearly those of Pyroxene, to which 

 species this mineral will probably be found to 

 belong. . 

 amorphous. 



