0.47 ct. Color Change Hackmanite
Color: Light Yellow / Dark Purple
Clarity: Slightly Included
Origin: Afghanistan
Cut: Oval Mixed
Treatments: None
Measurements: 5.4 x 5.9 mm
The single most remarkable example of color change in this species that we have ever encountered. Even with the original finds of Canadian material decades ago, stones that exhibited the color change under UV exposure (a property technically called tenebresence) were few and far between. Even the best of those never seen to have transitioned from colorless/light yellow to such a deep and saturated purple as we see here. The change takes about one minute under shortwave UV to reach maximum, the Amethyst-like color then gradually fading back to yellow. Longwave UV response is extreme as well - take a look at that in the last photo. This was cut to be as large as possible from a small fragment, it is slightly shallow and has a small veil, but honestly, the color change is the major star here. A remarkable stone and the only one like it that we have.