Ethiopian Emerald Analysis, Part II

Ethiopian emeralds have characteristics similar to other talc-mica-schist deposits such as those in Zambia and Brazil.

September, 2017

Using spectroscopic and chemical analysis, it has been reported that Ethiopian emeralds have unique characteristics which make this material distinguishable from other, global emerald origins.

Ethiopian emerald characteristics:

  • Colour ranges from light blue-green to intense saturated pure green
  • Have elevated Li, Na and Cs content compared to Brazilian emeralds, but the values are slightly lower than in emeralds from Zambia (Exhibit 1)
  • Low Fe contents when views against Li/Rb ratios (Exhibit 4) indicates a unique property that can help distinguish Ethiopian material from other sources
  • Very low vanadium contents compared to other emerald origins (Brazil, Zambia etc.)
  • High absorbance of Fe2+ at around 840 nm (Exhibit 5)

Exhibit 1 – Cesium / iron trace element concentrations plot (parts per million, log scale) across all major global emerald deposits

Ethiopian Emerald Analysis, Part II 3
Source: InColor ׀ Spring 2017, www.gemstone.org

Exhibit 2 – Lithium / cesium trace element concentrations plot (parts per million, log scale) across all major East-African emerald deposits

Ethiopian Emerald Analysis, Part II 3
Source: InColor ׀ Spring 2017, www.gemstone.org

Exhibit 3 – Lithium / zinc trace element concentrations plot (parts per million, log scale) across all major East-African emerald deposits

Ethiopian Emerald Analysis, Part II 3
Source: InColor ׀ Spring 2017, www.gemstone.org

Exhibit 4 – Rubidium-lithium / iron trace element concentrations plot (parts per million, log scale) across all major East-African emerald deposits

Ethiopian Emerald Analysis, Part II 3
Source: InColor ׀ Spring 2017, www.gemstone.org

Exhibit 5 – UV-visible absorption spectrum of an Ethiopian emerald – red line: ordinary ray, blue line: extraordinary ray

Ethiopian Emerald Analysis, Part II 3
Source: InColor ׀ Spring 2017, www.gemstone.org

To view our selection of emeralds then click on this link.

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