Influence of the liquid composition, concentration of the potassium acetate, substrate-liquid distance and liquid layer thickness on the diamond formation were surveyed under a constant current for deposition during 1 h. Optimum deposition conditions were found to be 0.1 mol % potassium acetate, 8 mm substrate-liquid distance and 10-20 mm liquid layer thickness. Diamond forming liquid composition was then examined under a constant substrate temperature. It ranged from 60 to 99.9 mol % ethylene glycol; end compositions showed a poor yield. A constant substrate temperature was maintained under a constant current for temperatures lower than 900 degrees C. However, an important current reduction was required during the deposition to keep the substrate temperature higher than 1000 degrees C.