Quartz – Natural, Rough, White

    A piece of rock crystal or colorless quartz cut into a wedge shape can help a gemologist conduct optic sign tests with a polariscope. "Quartz - Rock Crystal" by Lucky Lynda is licensed under CC By 2.0

    Article: How To Make A Quartz Wedge For Polariscope Testing

    Credit: Lucky Lynda

    Natural or man madeNatural
    Gem StateRough