Main color :
color due to iron, very light to dark purple, which is most wanted quality. Shades purple, lilac.
Color of streak :
2.63 to 2.65
varieties that are not gems of amethyst are translucent.
Refractive Index :
1.543 - 1.554
Double refraction :
Very small positive uniaxial
visible double refraction :
Number of colors :
From very low to definite, purple-red to purple-gray
Absorption spectrum : 550 - 520
Sometimes greenish or yellow-orange, according to sources.
stripes in rows, clumps of needle - like goethite, hematite, and cacoxénite and liquid inclusions. And also areas of colors in chevrons or straight more definite.
6-sided hexagonal prisms ending in pyramids.
Crystal system :
Astrological sign :
Aries, Taurus, Gemini, Cancer, Sagittarius, Aquarius, Pisces
Chinese astrological sign :