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ReferenceREFERENCE
Spessartite GarnetContribute a photo

Spessartite Garnet

スペサルタイトガーネット · すぺさるたいとがーねっと
NaturalYellow / Orange
Gemological dataPROPERTIES
Hardness7-7.5
Specific gravity4.12-4.20
Refractive index1.790-1.810
Crystal system等軸晶系
Color rangeCOLOR RANGE

Bright pumpkin orange, fanta-style pure orange, slightly reddish orange, and yellowish orange tones. The 'mandarin' grade is pure vivid orange without brown.

UV responseFLUORESCENCE
Long-wave
365 nm
Inert
Short-wave
254 nm
Inert
Typical inclusionsINCLUSIONS
  • nclusions
  • nclusions and partially healed fingerprints
  • nclusions in Nigerian material
Optical characterOPTICAL TRAITS
  • Singly refractive — no
  • No dichroism
What to look forID POINTS
  1. 01Inert UV plus pure orange in a singly refractive stone is the spessartite signature
  2. 02SG above 4.1 separates it from most other orange stones
  3. 03nclusions distinguish it from rutile-included orange sapphire
Stones it gets mistaken forSIMILAR STONES
Hessonite Garnet
Hessonite Garnet
ヘソナイトガーネット
Hessonite shows a syrupy 'heat-wave' or treacly pattern and warmer brown undertones. Spessartite is cleaner and more pure orange.
Orange Sapphire / Padparadscha
Orange Sapphire / Padparadscha
オレンジサファイア／パパラチャサファイア
Orange sapphire is doubly refractive, often shows , and is harder (Mohs 9). It also costs significantly more for top color.
Care & handlingCARE
  • Mohs 7–7.5 — durable for daily wear
  • Ultrasonic and steam are safe for clean stones
  • Avoid hard impacts
Market notesMARKET
PRICE RANGE

Roughly $200–$1,000 per carat for commercial yellowish-orange material, $1,500–$4,000 per carat for fine 1–3 ct mandarin grade, and $5,000–$10,000+ per carat for top pure-orange stones over 5 carats.

Note: No standard treatments — spessartite is sold as-mined. Color saturation drives most of the price spread: pure pumpkin-orange 'mandarin' material commands several multiples over yellowish or brownish stones. Clean stones over 3 carats are scarce.

BackgroundBACKGROUND

Spessartite (also written spessartine) is manganese-aluminum garnet (Mn₃Al₂(SiO₄)₃) colored orange to red-orange by manganese itself. Named after the Spessart Mountains in Bavaria, it was a rare collector's stone until major Namibian (1991) and Nigerian (1999) finds brought it to mainstream jewelry. Most modern stones are sold under the trade name 'mandarin garnet' for the purest pure-orange material.

Origin & historyORIGIN & HISTORY

Origins

Germany's Spessart Mountains gave the species its name in 1832, though that source never produced gem material. Namibia's Kunene region opened a major deposit in 1991, branded 'mandarin garnet,' with a pure neon orange that defined the modern look. Nigeria's Oyo State (1999) followed with similar saturated material sometimes called 'fanta garnet.' Mozambique, Sri Lanka, Myanmar, Brazil and California (USA) round out the market, but Namibian and Nigerian stones still set the price benchmarks.

History

For most of the 19th and 20th centuries spessartite was a collector's curiosity. The 1991 Namibian discovery turned it into a commercial gemstone almost overnight — Tiffany & Co. featured it, and the 'mandarin garnet' name took off in the trade. Both Namibian and Nigerian deposits have been mined hard since, and supply has tightened again over the past decade.

Lore & symbolism

January's birthstone alongside other garnets. Spessartite's vivid orange has come to symbolise vitality, courage, and creative energy — themes that fit a stone the color of sunrise.

OBSERVATION TOOLS · 1 ITEMS

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References
最終確認日
2026年4月28日
参 考 文 献

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