TECHNOLOGY FOCUS - INORGANIC CHEMISTRY - Preferred Property: The electroconductive powder has brightness index L-value in CIE 1976 Lxaxb color space is 25-85, where a and b values are psychometric-chroma-coordinates, 1-40. The pH of the liquid after preliminary neutralization is 2-3, and after neutralization is 7-12, preferably 6-12. Preferred Shape: The electroconductive power is cylindrical or acicular shape having long axis diameter of 500 nm or less, short axis diameter of 100 nm or less and axial ratio of 1.5-10, and ball shaped or grain shaped with particle diameter of 200 nm or less. Preferred Condition: The temperature at the time of preliminary neutralization is 45degreesC or less, and at the time of neutralization is 50degreesC or more, preferably 10-70degreesC. The heat processing temperature of the tin containing indium hydroxide is 300-1000degreesC. EXAMPLE - Hydrochloric acid solution (in g) (200) containing 18 wt.% of indium was diluted with pure water (2.9 l). Further chlorinated tin (II) (5.4) was added to the acid solution, and indium and tin containing acidic solution was produced. Gold (0.3) was dissolved in aqua regia, and gold containing solution was produced. Sodium hydroxide solution (108.2) was diluted in pure water (890) and an alkali solution was produced. A portion of the alkali solution was added to indium and tin containing acidic solution at 20degreesC for 15 minutes, and preliminary neutralization was carried out at pH of 3. Subsequently, the temperature was raised to 90degreesC, and alkali solution and gold containing solution were added for 40 minutes. The pH was adjusted to 10 and the obtained liquid was filtered. The precipitate was dehydrated and dried to obtain precipitate of gold and tin containing indium hydroxide. The obtained precipitate had long axis diameter of 135 nm, short axis diameter of 24 nm and axial ratio of 5.6. The precipitate of gold and tin containing indium hydroxide was bake processed at 600degreesC for 2 hours in nitrogen atmosphere containing 1.5 volume% of water vapor and 0.05 volume% of ammonia gas. Stabilizing treatment was then performed by cooling the product from calcination temperature to room temperature in air, to obtain electroconductive powder. The powder had long axis diameter of 125.63 nm, short axis diameter of 31.74 nm, axial ratio of 3.9, and specific surface area of 26.8 m2/g.