Abstract
The Bruçó granite outcropping in the NE of Portugal, is a porphyritic two-mica granite having associated, near the border of the massif, some pegmatites with tourmaline and quartz veins with W mineralization. Composed mainly of quartz, plagioclase, potassium feldspar, muscovite, biotite, and accessory minerals such apatite, chlorite, sericite, zircon, ilmenite, monazite, rutile, and tourmaline. Its paramagnetic behavior is primarily attributed to the presence of biotite and ilmenite, categorizing it as an "ilmenite type" granite. Variations in its biotite content and tourmaline, influence its magnetic properties and ellipsoid shape. The granite's AMS fabric aligns with the Moncorvo-Bemposta shear zone, indicating its emplacement during active tectonic activity. Geochemical analysis classifies it as a peraluminous granite. Despite its spatial association with tungsten mineralization, the Bruçó granite does not exhibit specialization in tungsten. Analysis of REE spectra reveals consistent behavior, influenced by accessory minerals like zircon, leading to fractionated spectra. Comparisons with other two-mica granites from Central Iberian Zone highlight its unique titanium content and mineral composition, aiding in understanding granitic patterns and classifications.