Pronounced u-art, and short for universal asynchronous receiver-transmitter, the UART is a computer component that handles asynchronous serial communication. Every computer contains a UART to manage the serial ports, and some internal modems have their own UART.
1 Color. 2  Color of a rock depends on the minerals present and on their grain size. 3  Generally, rocks that contain lots of feldspar and quartz are light colored, and rocks that contain lots of pyroxenes, olivines, and amphiboles (ferromagnesium minerals) are dark colored.
Thus, ferruginous quartz can often be found in sedimentary rocks in and near hydrothermal veins and in the iron hat (the weathering zone near the surface that is altered by oxidizing surface waters) of iron ore deposits.