Hackmanite natural crystal 154g, Afghanistan

During the day it looks like some kind of salt crystal, and at night it fascinates anyone who sees it with a strange luminescence. This stone is called hackmanite, and its extraordinary abilities have long been a mystery to scientists.
Hackmanite has a light to dark purple color just after mining, but as soon as it is exposed to sunlight, the color quickly disappears and changes to gray or green-white. When placed back in a dark room or when exposed to shortwave UV light, the purple color slowly returns. A color change can occur within a few seconds when exposed to sunlight, but it can sometimes take up to a week to return to the original color. This effect can be repeated continuously, but is permanently destroyed by high heat. Some hackmanites (from Afghanistan and Burma), on the other hand, initially have a creamy white color, but in sunlight they turn purple to pinkish-red, which can fade again if left in a dark environment for some time. Under UV light, it then glows pink-orange.