450 
DESCRIPTIVE MINERALOGY. 
CUMMINGTONITE* 
Colour greyish white. In fine needles and tufts of imperfect crystals. Lustre silky. 
Opaque. Hardness 6.5. Sp. gr. 3.20. Infusible before the blowpipe. Composed of silica 
56.54, protoxide of iron 21.67, protoxide of manganese 7.80, soda 8.44, volatile matter 3.18, 
Cummington and Plainfield in Massachusetts. 
DANBURITE.f 
Colour shades of honey-yellow. Crystallized. Primary an oblique rhombic prism. Lustre 
highly vitreous. Transparent. Hardness 7.5. Sp. gr. 2.83. Phosphoresces before the 
blowpipe, and fuses into a white blebby transparent glass. Composed of silica 56.00, lime 
28.33, alumina 1.70, y.ttria ? 0.85, potassa (with soda?) and loss 5.12, water 8.00, 
Danbury, Connecticut. 
DYSLUITE4 
Colour yellowish or greyish brown. Crystallized. Primary the regular octahedron. Lus¬ 
tre vitreous, inclining to resinous. Nearly or quite opaque. Hardness 7.05. Sp. gr. 4.55. 
Before the blowpipe, it assumes a red colour, but does not melt. Composed of alumina 
30.49, oxide of zinc 16.80, peroxide of iron 41.93, protoxide of manganese 7.60, silica 2.97. 
Sterling, New-Jersey, with franklinite and troostite. It has been thought to be identical 
with automalite. 
ELECTRIC CALAMINE. 
Siliceous Oxide of Zinc. Cleaveland. 
Colour usually white or yellow. Crystallized and massive. Primary a right rhombic 
prism. M on M' 108° 40b Lustre vitreous. Transparent to opaque. Hardness 5.0. 
Sp. gr. 3.30 to 3.60. Infusible before the blowpipe. Composed of oxide of zinc 66.83, 
silica 24.89, water 7.46. 
Jefferson county, Missouri, with galena and other lead ores. 
EREMITE.§ 
Colour between clove and yellowish brown. Crystallized. Primary a right oblique angled 
prism. M on T 140° 30h Lustre resinous to vitreous. Semi-transparent. Hardness 5.0 
to 5.5. Sp. gr. 3.71. Infusible by the blowpipe, but becomes transparent and colourless. 
Watertown, Connecticut, in a bowlder of albitic granite. 
* Thomson. Outlines of Mineralogy, 4’c- 
it Shepard. American Journal of Science. XXXV. 137. 
J Thomson. Outlines of Mineralogy, fyc. 
1) Shepard. American Journal of Science. XXXII. 341. 
