Provenite

Jos Plateau

AreaDraft data

9.5667° N, 9.0833° E · Region only

Aquamarine and Emerald from Plateau State, Nigeria, with photos of specimens from this locality.

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Minerals found here

AquamarineEmerald

Aquamarine at Jos Plateau

Complete gem aquamarine crystal 5 cm long with a steep termination from the Jos Plateau, Nigeria.
Complete gem aquamarine crystal 5 cm long with a steep termination from the Jos Plateau, Nigeria.
Photo: Robert M. Lavinsky · CC BY-SA 3.0 · Source
Terminated gemmy aquamarine crystal 4 cm long from Jos, Nigeria.
Terminated gemmy aquamarine crystal 4 cm long from Jos, Nigeria.
Photo: Robert M. Lavinsky · CC BY-SA 3.0 · Source
Richly coloured blue aquamarine crystal 4.2 cm long from the Jos Plateau, Nigeria.
Richly coloured blue aquamarine crystal 4.2 cm long from the Jos Plateau, Nigeria.
Photo: Robert M. Lavinsky · CC BY-SA 3.0 · Source
Slender gem aquamarine crystal 6.7 cm long with a sharp termination from the Jos Plateau, Nigeria.
Slender gem aquamarine crystal 6.7 cm long with a sharp termination from the Jos Plateau, Nigeria.
Photo: Robert M. Lavinsky · CC BY-SA 3.0 · Source
Bullet-shaped gem aquamarine crystal 3.3 cm long from the Jos Plateau, Nigeria.
Bullet-shaped gem aquamarine crystal 3.3 cm long from the Jos Plateau, Nigeria.
Photo: Robert M. Lavinsky · CC BY-SA 3.0 · Source
Formula
Be₃Al₂Si₆O₁₈
Morphology
Slender prismatic gem crystals with steep pyramidal terminations, some bullet-shaped
Typical size
About 2-7 cm long
Color / luster
Light to rich blue, gemmy, glassy
Availability
Unknown
History
Many specimens come from finds of the mid-1980s

Sources: SRC-749 SRC-266

About Aquamarine →

Emerald at Jos Plateau

Very transparent but light, bluish-green crystals with zoned colour

Light green emerald crystal of 2.7 cm with a modified pinacoid termination from Jos, Nigeria.
Light green emerald crystal of 2.7 cm with a modified pinacoid termination from Jos, Nigeria.
Photo: Robert M. Lavinsky · CC BY-SA 3.0 · Source
Doubly terminated transparent emerald crystal of 3.9 cm from Jos, Nigeria.
Doubly terminated transparent emerald crystal of 3.9 cm from Jos, Nigeria.
Photo: Robert M. Lavinsky · CC BY-SA 3.0 · Source
Transparent light green emerald crystal of 2.3 cm with a smaller attached crystal, Jos, Nigeria.
Transparent light green emerald crystal of 2.3 cm with a smaller attached crystal, Jos, Nigeria.
Photo: Robert M. Lavinsky · CC BY-SA 3.0 · Source
Bluish-green emerald crystal from the Jos area, Nigeria.
Bluish-green emerald crystal from the Jos area, Nigeria.
Photo: Robert M. Lavinsky · CC BY-SA 3.0 · Source
Formula
Be3Al2Si6O18
Morphology
Slender hexagonal prisms with flat or modified pinacoid terminations, some doubly terminated
Typical size
Crystals about 2-4 cm long
Color / luster
Light green to bluish green, often zoned; highly transparent, vitreous
Trace elements
Some crystals are iron-rich, which gives a bluish tint

Sources: SRC-824 SRC-825

About Emerald →

Geology of the locality

Setting
Plateau of older Cambrian-Ordovician granites intruded by tin-bearing Jurassic Younger Granites, with Pliocene and later basalts
Region
Plateau State
Country
Nigeria

Labels give only the Jos Plateau. Coordinate is the reference point of the Jos Plateau article on Wikipedia; regional only.

Sources: SRC-748

Sources

  1. SRC-748 · Website
    Jos PlateauWikipedia contributors · Wikipedia
  2. SRC-749 · Website
    File:Beryl-163183.jpgRobert M. Lavinsky · Wikimedia Commons
  3. SRC-266 · Book
    Handbook of Mineralogy - BerylAnthony, J.W.; Bideaux, R.A.; Bladh, K.W.; Nichols, M.C. · 2001 · Mineralogical Society of America / Mineral Data Publishing
  4. SRC-824 · Database
    Jos Plateau, Plateau, NigeriaGemdat.org (citing Kievlenko, E.Ya. 2003, Geology of Gems) · Gemdat.org (Hudson Institute of Mineralogy)
  5. SRC-825 · Website
    File:Beryl-49541.jpg (Wikimedia Commons)Robert M. Lavinsky · Wikimedia Commons

Draft data from the Provenite workbook. Check entries against the cited sources before relying on them. Photos are open-licence images from Wikimedia Commons; the author and licence are given with each photo.