The surface boundaries of the lode must be marked by eight substantial posts hewed or blazed on the side facing the claim and plainly marked with the name of the lode and the corner, end, or side of the claim that they respectively represent and sunk in the ground as follows:

1.    One at each corner.

2.    One at the center of each side line.

3.    One at each end of the lode.

If it is impracticable on account of rock or precipitous ground to sink such posts, they may be placed in a monument of stone.