ShangrilaGems ‘The Best Gems on the Web!’ Gem-A Corporate Member Pay post for one item and have up to 10 sent for free. Item will be sent by Airsure track and trace speed post. You will be sent a tracking number. Uk customers will receive a shipping refund. 3mm to 4mm AAA 16" LINE Watermelon Tourmaline beads AAA Grade - sale for one 16" line only.For those looking for top quality - these are an absolute bargain - look at the color and the clarity! We are corporate members of the British Gemmological association. We are totally honest about the treatment of all our gemstones. Please read our terms and conditions before bidding. Many thanks. Tourmaline Gemstone InformationTourmaline is an extremely complex borosilicate that occurs in every color; more than 100 colors and still counting! Therefore a range of chemical compositions occur; also many individual crystals show zones of multiple colors.Tourmaline HistoryThe West was introduced to Tourmaline in 1702 when the Dutch first imported it from Ceylon. Specfications of TourmalineHardness on Mohs Scale: 7-7.5 Toughness: Good Luster: Vitreous Specific Gravity: 3.0-3.1Refractive Index: 1.62-1.65Cleavage: Difficult/Indistinct General Chemical Formula: Various - It is a complex boro-silicate of Aluminium, Magnesium, Iron and copper.-