This listing is for a 50g bag of raw Hackmanite crystal pieces, with each piece measuring approximately 1.5-3cm in size. Originating from Afghanistan, these polished Hackmanite crystals offer a natural shape that reacts to UV light. Hackmanite is a unique mineral that displays a vibrant colour when exposed to UV light, making it a desirable collectable for crystal enthusiasts. Each piece is unmodified and in its natural state, adding to its authenticity and appeal.

Hackmanite is a rare, sulfur-rich variety of sodalite known for tenebrescence, its ability to dramatically change colour when exposed to sunlight or UV light and then revert to its original hue in the dark. Typically colourless or white when freshly mined, it often turns vibrant pink, violet, or raspberry-red in UV light and fades back in sunlight or darkness.

Valued by collectors for its unique optical properties, it's found in locations like Afghanistan, Greenland, and Russia, with gem-quality stones being especially rare.

Key Properties

Mineral Family: Sodalite

Chemical Formula: Na₈Al₆Si₆O₂₄Cl₂

Hardness: 5.5–6 on the Mohs scale

Colour Change (Tenebrescence): Fades to white/colourless in light, redevelops colour (often pink/purple) in the dark or under UV light.

Phosphorescence: Can glow in the dark after UV exposure.

Colour Variation & Reversal

Freshly Mined: Can be pale violet (Greenland/Canada) or creamy white (Afghanistan/Myanmar).

UV Exposure: Develops intense pinks, purples, or reds.

Sunlight/Darkness: Fades back, though the process can take hours or days. Heat permanently destroys this effect.

Gemology: A fascinating natural phenomenon, making it popular with mineral collectors.

Metaphysical: Believed to enhance intuition, self-expression, and balance.

Origin: Named after Finnish geologist Victor Axel Hackman.