Non-integral hybrid ions in tourmaline: buffering and geo-thermometry
The tourmaline group of minerals is indeed an enigma. Experimental data from optical spectroscopy, electron microscopy, and Mossbauer spectroscopy reveal a host of physical properties that lack a common structural clarification. For example, tourmaline samples change colour when irradiated with X-ray and gamma-ray radiations some reverting back when heated in air; exhibit simultaneous oxidation an