A shear-mode piezoelectric accelerometer using YCa4O(BO 3)3 (YCOB) single crystal was designed, fabricated and successfully tested for high temperature vibration sensing applications. The prototyped sensor was tested at temperatures ranging from room temperature to 1000 C and at frequencies ranging from 80 Hz to 1 kHz. The sensitivity of the sensor was found to be 5.7 pC/g throughout the tested frequency and temperature range. In addition, YCOB piezoelectric accelerometers remained the same sensitivity at 1000 C for a dwell time of four hours, exhibiting high stability and reliability. © 2011 American Institute of Physics.