MAHENGE SPINELS

Mahenge spinel takes its name from a town in central Tanzania, in the Morogoro region. In the summer of 2007, miners on the neighbouring hill of Ipanko uncovered spectacular crystals — some weighing several dozen kilos — which yielded a pink of an intensity never seen before. Since then, the term has referred both to this precise origin and to the degree of saturation that made it famous: a radiant, almost neon pink that has become one of the absolute benchmarks in the world of coloured gemstones.

From traces of chromium within the crystal lattice, enhanced by a decisive characteristic of the deposit: the near-total absence of iron. Without iron to mute it, chromium emits red fluorescence under the ultraviolet component of daylight — the stone literally reflects more pink light than it receives. It is this physical phenomenon, rather than an effect of cutting, that produces the celebrated neon effect, sometimes shaded with raspberry or a hint of orange.

No. Spinel is among the rare gems that the market almost never treats: no heating, irradiation or oiling. The ten Mahenge spinels currently listed in our catalogue all carry the “no treatment” designation on their product page. The colour you see is the one that formed in Tanzanian marble hundreds of millions of years ago — and it will not change.

The chemistry, and therefore the light. Pink spinel from another origin generally contains some iron, which greys the hue and softens its brilliance; Mahenge material is almost devoid of it, allowing the full vibrancy of chromium to emerge. The difference is visible indoors: take both stones out of direct light, and Mahenge continues to radiate while classic pink becomes more subdued. This performance in low light accounts for the difference in value between the two families.

Yes, and this is one of its greatest advantages. With a hardness of 8 on the Mohs scale and no cleavage planes, the stone withstands everyday wear for decades with no precaution beyond having the setting checked every two years. And because its colour is never treated, nothing can deteriorate over time — no resin to yellow, no furnace colour to wear away. Few coloured gemstones offer such peace of mind.

A bath of warm soapy water, a soft brush and drying with a soft cloth: the complete routine takes two minutes. Simply avoid harsh chemicals and store the jewel in its case, away from diamonds that could scratch its polish. Ultrasonic cleaning is suitable for a sound stone; if in doubt, entrust the jewel to us — inspections are complimentary for life on our creations.

Our ten listed stones range from €10,469 to €18,600, for weights of 1.59 to 2.67 carats — a consistent level of around €6,900 per carat, with only one stone falling below €6,000. This positioning reflects the market: Mahenge is now the most highly valued origin for pink spinel, driven by production declining since its 2007–2008 peak and sustained international demand.

By the certificate, never by someone’s word. Laboratories do not issue a “Mahenge” designation as such: they determine an origin — Tanzania — from the stone’s inclusions and chemistry, with some adding a colour comment such as “vibrant pink”. Each of our stones is listed with this origin determination and its complete file: precise dimensions, photographs and videos under several lighting conditions.