These small spiny creatures are endemic to the coastlines of New Zealand. The bright orange roe of kina is a delicacy, and considered a Taonga by many Maori.
My original master Kina shell was fabricated with Repousse and Chasing (some of the oldest techniques in silversmithing).

Sterling silver lightweight half Kina shell. Measuring approximately 17mm in diameter.
Suspended from a 45cm/18 inch sterling silver chain, with hook closure.

Jade Kina: Sterling silver, hand painted with porcelain paint

The porcelain paint is water and scratch resistant.