Amethyst Rough - Gem Decor Amethyst rough. This Amethyst was mined from the Norcross- Madagascar (NMG) Amethyst mine. You will receive Amethyst Tumble Rough (5-30g) with this order. Typical applications include: Amethyst rough for rock tumbler, interior design projects, garden decor applications landscape works, designer pool and spa accents, designer aquarium projects, bulk commercial specimen applications. Further discounts apply for quantity purchasing. Pricing based on purchasing quantity.