
577 P.2d 1268 (1977)
Farris W. BLYTHE (James P. Blythe, sole heir, substituted) Pearl Johnston, nee Blythe and Elizabeth Anderson, Appellees,
v.
Jewel HINES, Appellant.
No. 48517.
Supreme Court of Oklahoma.
November 22, 1977.
Rehearing Denied May 3, 1978.
Reed, Hurst & McNeil by Phil S. Hurst, Sulphur, for appellees.
Charles Nesbitt, Oklahoma City, for appellant.
DOOLIN, Justice:
We granted certiorari on September 9, 1977, under Rule 3.15 of the Court of Appeals, 12 Ch. 15, App. 3. No application for additional briefs alleging good cause has been filed by either party; this matter will be decided on the briefs heretofore filed.
The facts are not disputed.
Upon the death of a "common ancestor," Tom F. Blythe, the real property of deceased descended in undivided interests to decedent's widow, Jewel Hines (defendant herein) and his mother, (plaintiff's grantor). Defendant and plaintiffs' grantor effected a voluntary partition of the subject land, the effect of which we are called upon to determine. In July of 1959, the parties exchanged deeds and other valuable consideration between themselves, affecting various tracts of the common ancestor.
The Special Warranty Deed1> creating the interest of the party, states in pertinent *1269 part that the defendant grants, bargains, sells and conveys to plaintiffs' predecessor in title all her right, title and interest, "in and to the surface estate" to the questioned real properties. The description then follows, as well as an habendum and other usual clauses. Execution, signature and acknowledgment are not in question.
The plaintiffs, who as successors in title to original grantor, brought a quiet title action in November of 1975, against the defendant widow claiming the deed in question vested title to the sand, gravel, limestone and rock in, upon and underlying the questioned property in them.
We must determine what interests were created by the grant of the surface estate.
The trial court found the limestone was an integral part of the surface estate; that the granting words were not ambiguous and therefore parol or extrinsic evidence should not be allowed or considered as to the intent of the parties to the partition. The Court of Appeals affirmed.
We do not fully agree with the trial court or the Court of Appeals.
We are of the opinion the recent case of Riedt v. Rock Island Improvement Company, 521 P.2d 79 (Okl. 1974) is controlling when an interpretation of grants or reservations of mineral and surface is made. The case says, at page 83:
"In determining what the parties intended by a contract, the court should, as far as possible, place itself in the position of the parties when the contract was made, and to the extent that their mutual intention is ascertainable and lawful, give effect thereto. King-Stevenson Gas & Oil Co. v. Texam Oil Corp. (1970), Okl., 466 P.2d 950. It is the primary concern of the parties to which we will look (Panhandle Co-operative Royalty Co. v. Cunningham (1972), Okl., 495 P.2d 108, 115), recognizing that it is settled law in this jurisdiction that the cardinal rule to be applied in construing deeds is to ascertain the intent of the parties (Birmingham v. McCoy (1961), Okl., 358 P.2d 824) as that intent may be discerned from the instrument itself, taking it altogether, considering every part of it, and viewing it in light of the circumstances existing at the time of its execution. Lahman v. Bassel (1962), Okl., 373 P.2d 245. Dwelle v. Greenshields (1957), Okl., 305 P.2d 1038.
* * * * * *
In sum, assuming that the word "surface" as used in the deed here is uncertain, and this court has recognized that it has been so held by other courts in different situations, Mack Oil Company v. Laurence, Okl., 389 P.2d 955 the modern tendency is to treat all uncertainties in a conveyance as ambiguities to be clarified by resort to the intention of the parties as gathered from the instrument itself, the circumstances attending and leading up to its execution, and the subject matter and the situation of the parties as of that time (23 Am.Jur.2d 159), and that is what we shall do."
We conclude that under the facts in this case the grant of the "surface estate" with no reservation of minerals, oil and gas or any previous conveyance affecting any portion of the fee simple title was ambiguous.2 In a definitive work concerning Oklahoma mineral estates, "What Surface is Mineral and What Mineral is Surface?" The author3 concludes:
"1. In the light of adjudications, elsewhere, over these terms and the recognition of certain of them by the Supreme *1270 Court of Oklahoma, "mineral" and "surface" are regarded as ambiguous and uncertain in their scope, except that in a popular sense and within limits, "surface" is definite to an extent, in that, standing alone, it has always meant at least that part of the land devoted to agricultural and grazing purposes, and "minerals" is definite to an extent, in that it has meant, for a considerable period, those substances recoverable from the earth for profit by conventional shaft mining processes.
2. Beyond the limits set forth in paragraph 1 a
