Nuummite – What kind of stone is it?

Understanding the Colour Play

Greenlandic Stones in Stock: We sell Tugtupite, Nuummite, Kakortokite, Greenlandic Rubies, and finished jewellery online and at our store on Nybrovej 83 in Gentofte.

Facts, Folklore, and Tradition: We distinguish between documented geology, local folklore, and modern spiritual interpretations.

Fact-Based Reference Knowledge: Origin, mineralogy, colour, and hardness in one place – written for jewellery makers and collectors.

Why does Nuummite sparkle?

The play of colour is not due to pigment, but to light reflecting and refracting within the densely packed, elongated amphibole crystals. Because the crystals are oriented in specific directions, flashes are only visible from certain angles – this makes a nuummite cabochon appear 'alive' when rotated.

This also means that the direction of cutting is crucial. An incorrectly oriented cut can result in an almost entirely black stone with no colour play, even if the material itself is of good quality.

A Stone Named After Nuuk

Nuummite carries its origin in its name: Nuuk. The material was registered by mineralogist Karl Ludwig Giesecke in 1810, while the trade name Nuummite only became widespread much later. Its dark surface and short flashes of gold, copper, green, and blue mean the stone can appear almost opaque from one angle and vibrant from the next – a small piece of Greenland's approximately 2.7-billion-year-old bedrock.

In modern crystal spirituality, Nuummite is often associated with grounding, protection, intuition, and inner strength. These are symbolic, faith-based meanings without scientific documentation, not properties that Tomato guarantees the stone possesses.

Nuummite, nuummite, or nummite?

All three spellings are used interchangeably in trade for the same material. As Nuummite is a rock and not an approved mineral name, there is no single official mineralogical designation, and the name is also used for similar amphibole rocks from other localities. If the origin is important to you, it must be specifically stated in the product description.

Quality and Craftsmanship

• Good quality material shows colour play across the entire polished surface – not just in a single band.
• The width of the shimmering streaks varies; both fine and coarse patterns are found.
• The polish must be high, otherwise the colour play is noticeably subdued.
• Fissures and infillings occur and should be disclosed by the seller.

Buy Greenlandic Stones at Tomato

This page is written as reference knowledge for jewellery makers and collectors: what the stone is geologically, where it comes from, what it looks like, and what to be aware of regarding processing and authenticity.

We stock Greenlandic stones and finished jewellery made with them. You can find tugtupite, nuummite, kakortokite and raw Greenlandic rubies under Greenlandic Gemstones – available to buy online and view in our Gentofte store.

FAQ

Is nuummite a mineral?

No, it's a rock. It consists mainly of the intergrown amphibole minerals anthophyllite and gedrite, and their orientation gives it its iridescence.

How old is nuummite?

The material from the Nuuk area originates from the Archaean Eon and is among Earth's oldest known rocks – approximately three billion years old.

Is nuummite water resistant?

Yes, polished nuummite can withstand a brief rinse in lukewarm water. Avoid ultrasonic cleaners, soap and chemicals, which can attack fissures and infillings.