|Chemical composition||Silicon dioxide SiO2|
|Optic nature||Uniaxial +|
|Refractive index||1.544 - 1.553|
|Specific gravity||2.63 - 2.65|
|Pleochroism||Weak to strong|
Amethyst is a purple variety of the mineral quartz. It occurs in all intensities of the color purple from a light pastel to a depth of royal splendor. Until the beginning of the 20th century it was quite rare and costly. When vast deposits were found in Brazil, amethyst became very accessible and affordable. Amethyst has always been linked to the thinking process, ensuring clarity of vision. It inspires creativity, courage and valor. Amethyst has been successfully synthesized in the lab, so buyers need to be sure their source is qualified to separate natural from lab grown material.