A uniaxial dead weight creep apparatus has been designed to investigate the low stress, low strain‐rate rheologic behavior of refractory minerals. Displacement and displacement rate resolutions of 0.5 &mgr;m and 0.1 nm/s, respectively, on samples of 1.5‐mm cross section and 3.0‐mm length at temperatures up to 1900 K have been achieved. Oxygen fugacity is controlled to 0.1 log unit, load to 0.1 N, and temperature to 5 K. Maximum stresses applied were between 25 and 30 MPa. Use of this apparatus has allowed the investigation of the transient creep regime in olivine, an important mineral in the Earth’s mantle.