Color: colorless, light to dark purple, light yellow, medium to dark yellow, light to dark brown, brown, green to yellowish green, light to medium pink.
Amethyst: light to dark purple.
Topaz: light, medium to deep yellow.
Blue crystal: light blue, dark blue.Almost all blue crystals are synthetic.
Smoke crystal: light to dark brown.As Si4+ was replaced by Al3+ in the composition, [AlO4]4- chromatic center was produced by irradiation.
Green crystal: green to yellow-green.Color formation is associated with Fe2+, and there are few naturally occurring green crystals on the market, which are usually an intermediate product of amethyst as it heats to topaz.
Hibiscus stone: light to medium pink, lighter tone.Usually pink because it contains trace amounts of titanium (Ti).Can have transmission starlight effect.
Hair crystal: colorless, light yellow, light brown, etc., can be due to the rutile is often golden, brown red color, tourmaline is often gray black;Containing sun - derived stone and gray - green.