PURPOSE: To obtain an implement which has excellent heat resistance and chemical resistance and is particularly suited for use in experiments, by forming on the surfaces of the implement a thin layer of diamond-state carbon or a thin layer of diamond.

CONSTITUTION: On the surfaces of an implement made of glass or plastic, a thin layer of diamond (diamond-state carbon) is formed to obtain a chemical-resistant implement. Preferably, an apparatus for the production thereof comprises a reaction chamber 3 having therein a first electrode 4 which is cylindrical with its upper opening and a second electrode 7 which is rod-shaped and can be housed in the cylindrical electrode 4, said first and second electrodes being so positioned as to face each other. Further, the polarity of each of the electrodes 4 and 7 is made reversible. In the apparatus with such constitution, a carbon-source gas or a gaseous mixture of a carbon-source gas and a carrier gas is fed from an introducing aperture 1 to the reaction chamber 3 in which a vessel 6 has been set. Then, high frequency voltage is applied to the first and second electrodes 4 and 7 while the vessel 6 is being heated thereby forming carbon in its excited state from the gas. Owing to this, a thin layer of diamond (diamond-state carbon) is formed on the surfaces of the vessel 6. It is preferable that the pressure for this reaction be 10-7W10-3Torr and the heating temperature be from room temperature to 950°C.