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  • Growth striation and value

    I was looking at the tourmaline
    and started wondering to what degree the absence of the growth striation would affect the price / value of the stone.
    I wonder whether all the experts out there could shed some light on this little problem in particular and presence of "flaws" and their effects on gem evaluation in general.

  • #2
    hi, what you see in this particular Tourmaline(providing the photo is accurate) is what is known as "colour zoning" and are not flaws in the true sense. They will affect the value of the stone especially if they are visable to the naked eye.Pink Tourmaline are commonly heated,to improve colour, if the base material has uneven colour, the resulting zoning is more prominent.This effect is also often seen in Sapphire, especially from Thailand and Africa.

    regards Jeff
    Motherearth - Fine Jewelry and Gemstones