350 
POPULAR SCIENCE REVIEW. 
T. White Oriental Jade from China 
II. Green Oriental Jade from New Zealand . 
III. Oceanic Jade from New Zealand 
IV. Jadeite from China .... 
V. Jadeite from a celt found at Morbihan, France 
VI. Saussurite from L. Geneva 
sp. gr. 2-97 
. 3-015 
. 3-18 
. 3-34 
. 3-344 
. 3-4 
In addition to the minerals enumerated in this table, there 
are a few other substances which have occasionally been classed 
as jade. Thus, a mineral found at Rhode Island was formerly 
described as an American nephrite, but has been found on 
analysis to be only a very hard variety of serpentine, and is 
now distinguished as Bowenite. Many of the celts from 
Brittany are wrought in a material known as Fibrolite , which 
is a simple silicate of aluminium, but has been mistaken for 
jade. Again, a dark-coloured jade-like mineral, occasionally 
used for implements, is distinguished by Damour as Chloro- 
melanite; this is a ferric-aluminic silicate, notable for high 
specific gravity, which ranges from 3*4 to 3*6. Jasper, when 
of dark green colour, has not unfrequently been taken for jade ; 
but it need hardly be said that, though the two substances do 
not differ widely in their degrees of hardness, they are ex- 
tremely different in density. As the specific gravity of jasper 
is only about 2*6, we have an unfailing test by which it may be 
distinguished from every kind of jade. 
Excluding, however, such substances as jasper, which obviously 
have no right to claim a place in the jade family, there yet 
remains a number of ornamental stones which have been, and 
are still, popularly grouped together under the inclusive name 
of jade. Much as the mineralogist may desire to see these 
substances rigidly designated by their proper names, it must be 
borne in mind that their discrimination is by no means an 
easy task, especially to unscientific collectors of works of art, 
into whose hands the finest specimens usually fall. Specific 
gravity offers, perhaps, the easiest and surest means of diagnosis ; 
but to determine specific gravity is not always convenient, and 
may be impossible, as in the case of jade objects mounted in 
metal. Chemical examination is, of course, out of the question 
in ninety-nine cases out of a hundred. Hence it sometimes 
becomes difficult even for a mineralogist to determine with 
precision the real mineralogical nature of a given specimen. 
It is then that a vague name like jade may still be retained 
with advantage, its value depending, in fact, upon its very 
vagueness. Even the greatest stickler for scientific precision 
must admit that there are occasions when he is compelled to 
lay aside his scruples, and to make a ruthless sacrifice of 
Accuracy on the altar of Convenience. 
