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Watermelon Tourmaline

Pink core, green rind: a single elbaite crystal that changed chemistry as it grew.

Family
Tourmaline
Formula
Na(Li,Al)₃Al₆(BO₃)₃Si₆O₁₈(OH)₄
Mohs
7 to 7.5
System
Trigonal

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Science

Elbaite is lithium tourmaline, the species that carries almost every gem colour. Watermelon crystals grew with manganese early, then iron later, so a slice across the prism shows a pink centre inside a green shell. Cutters sell it as polished slices to keep the pattern.

Mineral
Tourmaline (variety)
Formula
Na(Li,Al)₃Al₆(BO₃)₃Si₆O₁₈(OH)₄
Crystal system
Trigonal
Mohs hardness
7 to 7.5
Specific gravity
3.03 to 3.10
Refractive index
1.624 to 1.644
Lustre
Vitreous
Colours
Pink, Green

Composition

Na(Li,Al)₃Al₆(BO₃)₃Si₆O₁₈(OH)₄. Made of Sodium, Lithium, Aluminium, Boron, Silicon, Oxygen, Hydrogen, with trace Manganese, Iron responsible for colour.

in formula trace, gives colour

Origin

  • Brazil
    Minas Gerais
  • United States
    Newry, Maine; Pala, California
  • Nigeria
  • Afghanistan
  • Mozambique

Filled dots are primary sources

Rarity

Uncommon
3 of 5

Sharp, clean bicolour slices are uncommon; most rough is cracked between the zones.

  1. 1 Abundant
  2. 2 Common
  3. 3 Uncommon
  4. 4 Rare
  5. 5 Exceptional

Hardness

Watermelon Tourmaline sits at 7 to 7.5 on the Mohs scale. It will scratch glass and holds a polish in daily wear.

Fingernail
Copper coin
Knife, glass
Steel file
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Energy

Associations from crystal-healing tradition, recorded here as folklore. They are not medical claims.

Chakras

  • Heart

Element

  • Water

Zodiac

  • Gemini
  • Virgo
  • Libra

Planets

  • Venus

Properties

  • Emotional balance
  • Joy
  • Reconciliation
  • Heart healing

Lore

The first crystals were found in Maine in 1820 by two boys at Mount Mica, the beginning of American gem mining. Tiffany sold Maine tourmaline for decades.

The 1989 Newry find in Maine produced over a tonne of gem tourmaline. Modern practice reads the pink and green as the heart's two colours in one stone.

  • Pleochroism
    Colour deepens when viewed down the length of the crystal.
  • Paraíba
    Copper-bearing elbaite from Brazil, the most expensive tourmaline.