25.33 ct. Greenland Hackmanite
Color: Medium Dark Purple
Clarity: Opaque
Origin: Narsaq, Greenland
Cut: Oval Cabochon
Treatments: None
Measurements: 41.2 x 16.6 mm
Always a fascinating gem material, this Hackmanite cab is from a slightly more unusual locale than the famous Canadian material. As you may know, Hackmanite is the name for the variety of the mineral Sodalite which reacts with a color-chage to UV light - a process called tenebresence. This Narsaq material behaves a bit differently - rather than being colorless in standard lighting it has a light 'aqua' green hue that is quite attractive in its own respect. It is, of course, intensely fluorescent (see the right photo above - a vivid orange) and will change to a deep reddish-purple after exposure to shortwave UV. The tenebresence seems far stronger than most of the material from Afghanistan and Pakistan that is of more recent vintage than most of the older Canadian stones. A large and quite fascinating stone to play with.