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
Rock concert Rock concert A rock concert is a musical performance in the style of any one of many genres inspired by "rock and roll" music. While a variety of vocal and instrumental styles can constitute a rock concert, this phenomenon is typically characterized by bands playing at least one electric guitar, an electric bass guitar, and drums. Often, two guitar players share the tasks of rhythm and lead guitar playing. Rock concerts also have a social history which shapes the perception of the linguistic term and the activity itself. During the 1950s, several American musical groups experimented with new musical forms