The dropsied is named after the words "say" and
"posies" meaning double vision. The Greek root has been assigned
because of its strong birefringence which causes a splitting of the pavilion
facets when viewed through the table. The gem-quality dropsied generally has a
very dark green which is caused by the presence of chromium. The stones that
resemble it are emerald, peridot and tourmaline. Its main sources are mining in
South Africa , Brazil , Sri Lanka ,
Madagascar and Finland
Characteristic
Chemistry: Ca Mg
(SiO3) 2 (Silicate of calcium and magnesium).
Color: Light
green to dark green, yellow, colorless.
Hardness: 5.0 -
6.0
Specific gravity:
3.30
Refractive index:
1.67 - 1.72
Dispersion: None
Polychrome:
yellow-green, olive green.
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