Bond percolation threshold is calculated for lattices with hexagonal symmetry, using the transformation triangle - star and the duality of lattices. This calculation is exact and widely well - known especially for triangular and hexagonal lattices. This technique applied to Kagomé lattice in sites and bonds reproduces the percolation thresholds obtained by Scullard and Ziff. This procedure is enlarged to square lattice of bonds, being obtained the exact value of the percolation threshold. According to the simplicity of the utilized methodology, this can be applied to other plane geometries and possibly to 3D lattices.