Pounamu
Pounamu is a Maori word which is used to describe jade / greenstone and also bowenite. The Maori classified pounamu according to colour and named many varieties. Pounamu is broken down into 4 types: kahurangi, kawakawa, inanga and tangiwai.

Kahurangi is the rarest form of pounamu / greenstone. It is a light green greenstone with light streaks which resemble clouds. It is free of any flaws and is very translucent.

Kawakawa has a strong green colour with varying shades throughout. It is named due to the fact that it resembles a leaf from the kawakawa / Lofty pepper tree.

Inanga which means whitebait is a pearl white grey/green coloured stone which is usually translucent.

Tangiwai (Bowenite) is a very translucent, olive-green to bluish-green type of serpentine, found mainly at the entrance to Milford Sound in the South Island. The word tangiwai came from the Maori legend relating to the petrifaction of the tears of a lamenting woman. Sometimes it is referred to as koko-tangiwai, koko meaning ear pendant, and this signifies its predominant use. 

Acient Maori had no written language so tribal history and the stories of the gods were kept using many forms of fine arts and crafts ranging from basket and cloth weaving to complex wood, bone, shell and jade carving. These artefacts were then handed down through generations of tribal elders and became sacred objects or treasures "Taonga", telling the history of a tribe and taking on the spirits of past great leaders and warriors who had worn them.

It is believed that a carving which is worn with respect or given and received with love, takes on part of the spirit of those who wear or handle it. In this way it becomes a spiritual link between people spanning time and distance. A carving that has been worn by family or tribal members over many generations contains the spirit of all of those people and is truly a great and powerful treasure.

Therefore it is also believed that a greenstone pendant should be given to a special person and not to buy it for yourself as this is tapu (sacred) to be giving it to someone who has earned it. Therefore it is not done to give it to yourself.