Unless the deed to the property being purchased specifically excludes mineral rights, the presumption under the laws of all states in this country is that the mineral rights come with the property being purchased assuming the deed is a grant deed (warranty deed as opposed to a quit claim deed).Size of the parcel 1 acre (more or less) has no bearing on the ability to acquire mineral rights to the property being purchased. In short, the answer to your question is that a home buyer can purchase mineral rights along with a house if the property is less than an acre. For further answers to any other questions you might have, I suggest that you consult with a real estate attorney.