Beryl

 
Color : Gold, yellow-green, yellow, pink, colorless
Color of streak: White
Mohs� hardness : 7.5-8
Specific gravity : 2.67-2.71 
Cleavage : None 
Crystal system : Hexagonal
Chemical composition : Aluminium beryllium silicate
Refractive index : 1.570-1.600
Double refraction : -0.006-0.009
Flourescence : Morganite : weak ; violet

Golden Beryl
Yellow beryl. Color varies between lemon yellow and golden yellow. Pigment is probably iron. Inclusions are rare. Decolorization at 482 F / 250 C.

Heliodor
Color varies between lemon yellow and gold (�Present of the sun�). Apparently discovered in 1910 in Namibia, but similar stones had previously been known in Brazil and Malagasy Republic. Pigment is uranium oxide.

Morganite
Soft pink to violet beryl, also called pink beryl. Named after mineral collector J.P. Morgan in U.S. Specific gravity between 2.80 and 2.90. Lower color qualities can be improved by heating above 752 F / 400 C. 

Goshenite
Colorless beryl, named after a find in Goshen, Massachusetts (U.S.). Used as imitation for diamond and emerald, by foiling the cut stone with silver or green metal foil.