John Hardy. Bamboo 18k Gold Knot Ring, Size 7. A chaotic twist of bamboo-textured yellow gold gives this John Hardy ring a spirited feel that makes it ideal for happy hour and black-tie events alike. Not only will you look great, you'll feel great, too?thanks to your purchase of this cuff, there will be new bamboo plants. From the Bamboo Collection. 18-karat yellow gold knotted bamboo motif. Approximately 1" diameter. Handcrafted in Bali. About this collection:. The Bamboo Collection is a tribute to the beauty, strength, and versatility of bamboo. John Hardy is one of the first companies to take a position on global warming to offset the carbon emissions of its print advertising, business travel and electricity by planting bamboo in Bali. For each piece sold from the bamboo collection, a number of bamboo seedlings will be planted by John Hardy. By wearing Bamboo consumers help plant bamboo and declare their commitment to style and sustainability.