Tsavorite Garnet

East Africa's finest green garnet from Kenya and Tanzania - discovery, characteristics, and comparison with emerald.

By Fabian Moor Last updated
kenya tanzania tsavorite garnet grossular

Introduction

Tsavorite is a vivid green grossular garnet first discovered in Tanzania in 1967
and Kenya in 1971 by Scottish geologist Campbell Bridges, who was killed in 2009
defending his mine. Named after Kenya's Tsavo National Park, it is produced from
Pan-African metamorphic calc-silicate and graphite schist layers; the Tsavo region
of Kenya yields the finest material.

Tsavorite is coloured by vanadium and/or chromium, producing vivid green rivalling
fine emerald in colour saturation while surpassing it in brilliance (isotropic),
durability (hardness 7–7.5, no cleavage), and treatment status; virtually all
tsavorite is natural colour, making it unique among commercial green gems. The
primary limitation is size: stones above 2 ct are uncommon and those above 5 ct
are exceptional collector pieces commanding strong premiums. Fine tsavorite rivals
emerald per-carat value; the absence of treatment is a growing commercial advantage.
[1][2]

Discovery

The story of tsavorite's emergence:

  • Year: 1967 (Tanzania); 1971 (Kenya)
  • Discoverer: Campbell Bridges (Scottish geologist) [1]
  • Name: After Tsavo National Park, Kenya
  • Species: Grossular garnet (green variety)
  • Tragedy: Bridges was killed in 2009 defending his mine

Sources

Primary mining locations:

Kenya

  • Location: Tsavo area, near Tanzanian border
  • Status: Primary source for fine material
  • Mining: Small-scale operations predominate
  • Quality: Produces the finest colours

Tanzania

  • Location: Merelani area (also tanzanite source)
  • Status: Secondary but significant production
  • Character: Good quality material available

Characteristics

What makes tsavorite special:

  • Colour: Green (vanadium and/or chromium chromophore)
  • Saturation: Can rival finest emerald
  • Clarity: Often cleaner than emerald
  • Hardness: 7-7.5 (more durable than emerald)
  • No treatment: Virtually always natural colour [2]
  • Single refraction: Higher brilliance than emerald
  • Size limitation: Rare above 2-3 carats

Colour Range

Understanding tsavorite colours:

  • Finest: Vivid, saturated green comparable to emerald
  • Medium: Attractive green, good commercial material
  • Light: Mint green; less valuable but appealing
  • Yellowish-green: Lower grades; still attractive
  • Chromophore effect: Vanadium vs chromium affects exact hue

Tsavorite vs Emerald

Tsavorite

  • Single refraction (isotropic)
  • Higher brilliance
  • Often cleaner
  • More durable (no cleavage)
  • No treatment standard
  • Rare in large sizes (>2ct)

Emerald

  • Double refraction
  • Characteristic inclusions
  • "Jardin" expected
  • More fragile (cleavage)
  • Oiling nearly universal
  • Large sizes available

Size Rarity

Market Position

Tsavorite in the current gem market:

  • Value: Fine stones rival emerald prices
  • Advantage: No treatment required or expected
  • Appeal: Clean, brilliant alternative to emerald
  • Collector interest: Strong for fine specimens
  • Trade recognition: Well-established in gem trade

References

  1. ↑ 1. Schumann, W. (2009). Gemstones of the World (4th ed.). Sterling Publishing. ISBN: 978-1-4027-6829-3.
  2. ↑ 2. Read, P. (2014). Gemmology (3rd ed.). Butterworth-Heinemann. DOI: 10.4324/9780080507224.

Related Topics

East African Gems - OverviewGarnet GroupZambian Emerald