Synthetic quartz aggregates as a starting material for high-temperature / high-pressure deformation experiments were prepared using a high-temperature / high-pressure apparatus. Silica gel was prepared using a sol-gel method and subsequently dried and heated in air for three days at temperatures between 700 and 1000°C Various sets of the gels were then packed into Pt-Ni capsules with 0–2 wt% water and were sintered to form quartz aggregates at 800°C and 1 GPa for 5 hours. As a result, synthetic quartz aggregates with polygonal textures and very weak crystallographic preferred orientations were formed from a 1:4 mixture of two silica gels dried at 700°C and 1000°C, respectively.