This paper presents a little boron permeated on the surface of natural diamond to form boron skin with the ion implantation method. Tests are done to find whether its heat resistance might be Improved.A low-energy ion-implantation device has been designed and improved. Two sources (B2O3 and pure Boron) have been implanted to the natural diamond with four energies (8.0keV. 6.5keV. 4.5keV and 2.5keV). Boron-skin forms on the surface of diamond.The surface of diamond remains to be colourless and transparent af...