23. Zircon, Sapphire, Chrysoberyl, Chrysolite, Hiddenite,
and Tourmaline in Greenish Yellow
In
these stones yellow is usually the stronger in the first four, and the
green tint predominates in the latter. Individual characteristics are
generally sufficient to distinguish them. The zircon has the greatest
lustre, the sapphire is more transparent, chrysoberyl is usually
somewhat milky, and chrysolite is not so lustrous or transparent as the
zircon and sapphire.
Hardness. Specific Gravity. Dichroism.
Sapphire......9 3.9 to 4.1 Decided.
Chrysoberyl.. .8.5 3.68103.78 Weak yellow and green.
Tourmaline.. .7.25 3.1 Strong yellow and green.
Zircon........7.5 4.6 to 4.7 Very weak.
Hiddenite.....6.75 3.17 to 3.20 Weak, light and dark green.
Chrysolite.....6.75 3.33 to 3.37 Green and yellowish green.
24. Demantoid (Green Garnet), Epidote, Vesuvianite,
Sphene, and Andalusite (in Yellowish Green)
The
demantoid color is that of a fine emerald with a mixture of yellow.
Epidote tends to brown. Vesuvianite is seldom very transparent. Sphene
is rarely transparent. Andalusite inclines to reddish tint.
Hardness. Specific Gravity.
Demantoid . .6 to 6.5 3,83 Single refraction.
Andalusite...7.5 3.17103.19 Dichroism, strong; yellow,
green, red. Epidote.....6.5 3-47t0 3-5 Dichroism, strong; green,
yellow, brown. Vesuvianite. .6.5 3.35 to 3.45 Dichroism, green and yellow.
Sphene......5-5 3-35 to 3.45 Dichroism, decided.
25. Green Zircon, Sapphire, Chrysoberyl, Diopside, and
Tourmaline
The first two of these stones are very rarely seen. The specific gravity of the first and the hardness of the second
