Ametrine is a mix of both amethyst and citrine, and can be either natural, or artificially manufactured through heat treatment. Virtually all naturally occurring ametrine is found in Bolivia, hence it is sometimes known as bolivianite. It occurs in either typical quartz crystal form, or in massive form. The colors of both purple and yellow/orange [...]

Amethyst represents the violet or purple color, the color of enlightenment and attainment of higher self. It is a facilitator in transforming the lower level energies into higher oscillations of the spiritual realms. Amethyst is highly regarded as a spiritual tool by many crystal healers due to its more gentle effect compared to rock crystal, [...]

The amethyst is the world famous purple variety of the quartz family (SiO2). Amethyst occurs in crystalline form (usually in geodes) or in massive form (when the conditions for growth are not so conducive). Like quartz, amethyst has a hardness of 7 on the Mohs scale.
The color ranges from dark purple to almost faint lavender. [...]