Well, I listed these a few days ago and already they are going fast. Lovely bi and parti-colour tourmaline rose cut freeforms – also known as polki cut, if that makes more sense to you. The fascinating multi-coloured patterns that occur, and that make this material so unique are caused by changes in the concentration of trace elements during crystal growth. It is these trace elements that often give stones their different colours; manganese for red, pink or brown crystals, iron for dark blue or black, chromium for green and so on. As the crystal grows, if it is exposed to different trace elements, it will change colour as it grows. These are always so popular; partly due to their vibrancy, I think but also because they are unique. You can find them here, just in the Hong Kong store.