Unknown origin

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Showing 289–304 of 342 results

  • Tourmaline

    Tourmaline

    5,784 ct. | V/B
    GLA
    €1,500.00
  • Tourmaline

    Tourmaline

    6,245 ct. | IV/B
    GLA
    €1,600.00
  • Tourmaline

    Tourmaline

    6,441 ct. | IV/A
    GLA
    €2,200.00
  • Tourmaline

    Tourmaline

    7,247 ct. | V/C
    GLA
    €1,700.00
  • Tourmaline

    Tourmaline

    7,537 ct. | IV/C
    GLA
    €2,300.00
  • Tourmaline

    Tourmaline

    8,859 ct. | V/A
    GLA
    €2,700.00
  • Tourmaline

    Tourmaline

    10,417 ct. | V/B
    GLA
    €2,100.00
  • Tourmaline

    Tourmaline

    11,516 ct. | III/C
    GLA
    €3,200.00
  • Tourmaline

    Tourmaline

    12,282 ct. | V/A
    GLA
    €3,700.00
  • Tourmaline

    Tourmaline

    13,471 ct. | V/A
    GLA
    €4,600.00
  • Tourmaline

    Tourmaline

    37,686 ct. | IV/A
    GLA
    €12,500.00
  • Tourmaline

    Tourmaline

    4,28 ct. | V/D
    GLA
    €900.00
  • Tourmaline

    Tourmaline

    6,06 ct. | V/D
    GLA
    €1,000.00
  • Tourmaline

    Tourmaline

    16,269 ct. | III/B
    GLA
    €6,200.00
  • Tourmaline

    Tourmaline

    6,108 ct. | V/D
    GLA PGTL
    €900.00
  • Tourmaline

    Tourmaline

    3,524 ct. | VI/C
    GLA
    €500.00

Facts

properties of tourmaline

  • Separate mineralogical group with many varieties
  • Hardness grade 7 - 7,5
  • Chemical formula: XY3Z6(T6O18)(BO3)3V3W(V, W, X, Y, Z stand for different possible elements)
  • Includes all colors
  • Colored by different metal oxides
  • Specific gravity 2.8 - 3.3 g/cm3

origin

  • Brasilia
  • Madagascar
  • Pakistan
  • Various locations in Europe
  • Mozambique
  • Namibia
  • Nigeria

worth knowing

  • Oldest known locality in modern trade: Brazil
  • Occurs in all colors
  • Forms beautiful crystals with very good crystal endings
  • Various esoteric and healing meanings
  • Also large crystals and large cut stones possible
  • The locality Pakistan was discovered only around 2010

investment in tourmaline

  • Still undervalued compared to other gemstones.
  • Exception: the Paraiba tourmaline, which can be more expensive than sapphire
  • Stones should be at least 5 ct in weight, except for Paraiba
  • Larger stones have higher appreciation
  • Experts calculate 6 - 8% increase in value per year
  • Beautiful, pure stones with clear colors are preferable
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