All lands belonging to the territory of New Mexico, and all lands granted, transferred or confirmed to the state by congress, and all lands hereafter acquired, are declared to be public lands of the state to be held or disposed of as may be provided by law for the purposes for which they have been or may be granted, donated or otherwise acquired; provided, that such of school Sections Two, Thirty-Two, Sixteen and Thirty-Six as are not contiguous to other state lands shall not be sold within the period of ten years next after the admission of New Mexico as a state for less than ten dollars [($10.00)] per acre.