Pounamu

Pounamu is several types of hard, durable and highly valued nephrite jade, bowenite, or serpentinite found in New Zealand. Pounamu is the Māori name. The rocks are also generically known as "greenstone" in New Zealand English.

There are two systems for classifying pounamu. Geologically the rock falls into the three categories named above, but Māori classify pounamu by appearance. The main classifications are kawakawa, kahurangi, īnanga, and tangiwai. The first three are nephrite jade, while tangiwai is a form of bowenite.

• Īnanga pounamu takes its name from a native freshwater fish (Galaxias maculatus) and is pearly-white or grey-green in colour and varies from translucent to opaque.

• Kahurangi pounamu is highly translucent and a vivid shade of green. It is named after the clearness of the sky and is the rarest variety of pounamu.

• Kawakawa pounamu comes in many shades, often with flecks or inclusions, and is named after the leaves of the native kawakawa tree (Macropiper excelsum). It is the most common variety of pounamu.

• Tangiwai pounamu is clear like glass but in a wide range of shades. The name comes from the word for the tears that come from great sorrow.

In modern usage pounamu almost always refers to nephrite jade. Pounamu is generally found in rivers in specific parts of the South Island as nondescript boulders and stones. These are difficult to identify as pounamu without cutting them open.