Mandarin garnet

Mandarin garnet is the trade name for vivid orange spessartine, the manganese garnet. The name was first used for stones found in 1991 beside the Kunene River in north-western Namibia; today it is also used for any spessartine of that colour. Its bright orange comes from its high manganese content. When the Namibian deposit was exhausted, Nigeria, then Tanzania and Madagascar became the main sources. It is normally not treated at all; the purer its orange, the more it is worth, and stones over 10 carats are extremely rare.

Jewellery: hard, without cleavage and brilliant, it is set as a precious stone in rings, earrings and necklaces. Its vivid orange makes it one of the most striking garnets. Collecting: large, clean stones are rare and sought by collectors; specimens from the closed Namibian mine attract particular interest. Science: the proportions of spessartine, pyrope and grossular in stones from different deposits are measured to compare their sources.

It has a hardness of 7–7.5 on the Mohs scale. It scratches glass and steel; a steel knife cannot scratch it. Its specific gravity is 4.09–4.15 g/cm³.

Its best-known localities: Marienfluss valley and Kunene River, Kaokoland, Kunene Region, Namibia; Southwestern Nigeria; Nani, Loliondo, Ngorongoro, Arusha Region, Tanzania; Sahatany valley (Antsirabe area), Vakinankaratra, Madagascar; Zambia.

Its colour ranges from peach to vivid orange and reddish orange; the best show a pure, bright orange without any brown. It is a heavy stone: its specific gravity is 4.09–4.15, so hessonite (3.64–3.69) and citrine (about 2.65) of the same colour are clearly lighter. Its refractive index is about 1.79–1.80. Like other garnets it is singly refractive, has no cleavage and a hardness of 7–7.5. Inside, curved fibres or small crystals of minerals such as quartz, amphibole and barite may be seen. Orange glass and synthetic YAG (yttrium aluminium garnet made in the laboratory): used as imitations of mandarin garnet.

On the “street to diamond” value ladder it sits on step 7 of nine: Precious stone. Colour matters most for mandarin garnet: the purer and more vivid the orange, the more valuable the stone, while brown or red tones lower its value. Stones over 10 carats are extremely rare, so size raises value quickly. Clarity and a good cut also count. These stones are normally not treated at all; the real risk comes from imitations such as orange glass and synthetic YAG, so a laboratory report is important.

Today crystal-therapy websites link mandarin garnet with the sacral chakra because of its orange colour and claim that it brings joy, creativity, vitality and self-confidence. The same websites claim that the stone supports metabolism and blood circulation and strengthens the immune system. There is no scientific evidence that mandarin garnet brings joy or confidence, or that it affects metabolism, circulation or immunity; health problems call for a doctor. The stone was found only in 1991, so there is no old tradition of belief behind it; its orange colour is simply the result of the manganese it contains. This section reports beliefs; it is not health information. There is no scientific evidence for these claims and no stone replaces medical treatment.