Nephrite "hei-tiki" (neck pendant). These are believed to have their own "mana", are handed down as valuable heirlooms, and often given as gifts to seal important agreements. It has also been used for a range of tools such as adzes, as Māori had no metal tools before European contact. Commonly called "greenstone", jade jewellery in Māori designs is widely popular with tourists. Stone is often imported from Canada, China and Siberia, and Ngai Tahu runs a pounamu certification scheme to verify the authenticity of New Zealand stone. Nephrite Nephrite is a variety of the calcium, magnesium, and iron-rich amphibole minerals tremolite
Forms of juggling Some performers will mix various objects of widely differing weights, sizes, and shapes, requiring them to adjust their throwing force for each object. Instead of throwing balls, a juggler may roll them over the hands and body. Usually “crystal” balls (actually acrylic or plastic) are used. There are two distinct forms. A. Rolling one or two balls all over the hands, arms and body. B. Controlling three to eight balls, revolving them in stacks in the palms of the hands. Both forms often use the idea of "isolation". The impression is given of one ball being fixed in space and