New Mexico Statutes Chapter 4. Counties § 4-16-1. County boundaries

That a county, which shall be known as Luna county, is hereby created out of that portion of the territory of New Mexico included within the following boundaries, as indicated by United States survey, to wit: commencing at the northwest corner of township twenty-one south, range thirteen west of the New Mexico principal base and meridian; thence east along the north boundary line of township twenty-one south, to the southwest corner of township twenty south, range ten west; thence north along the west boundary line of range ten west to the northwest corner of township twenty south, range ten west; thence east along the north boundary line of township twenty south, to the northeast corner of township twenty south, range five west; thence south along the east boundary line of range five west to the international boundary line of the United States and the Republic of Mexico; thence west along said international boundary line, to the range line between ranges thirteen and fourteen west; thence north on said range line between ranges thirteen and fourteen west, to the northwest corner of township twenty-one south, range thirteen west, the place of beginning.