Ta-GRANITIC MICROTEXTURE

Ta-granite is peraluminous albite-granite with microlite and other rare-metal mineralizations. Believed to be a metasomatite mainly due to its complex texture, it is often called strongly albitized granite. However, microtextural criteria are unreliable to infer the order of initiation or cessation of crystallization for granitoids independently. Moreover, the metasomatism hypothesis is out of tune with either discovery of ongonite in Mongolia, or experimental melting/crystallization data in recent years. The last and relatively sepa-