Desperately need advice

My dad passed away a few years ago but in the 90’s he inherited land and mineral rights in Oklahoma when his mom passed. My step-grandfather filed a quit claim title for that land and mineral rights and on the quit claim there are two land descriptions. One states 25/70 interest in surface and mineral rights for S/2 SE/4 NE/4 and SE/4 SW/4 NE/4 of Section 26 Township 4 South, Range 2 East in Carter County, Oklahoma. The other says a 25/70 mineral right interest on E/2 NE/4 NE/4 and N/2 SE/4 NE/4 of Section 26 Township 4 South, Range 2 East.

I am told the 25 of the 25/70 represents the acres, so by what I read I would guess he owned a total of 25 acres in surface rights (which he sold in 1998, but retained ALL mineral rights to) and also owns a total of 50 acres of mineral rights between the two land descriptions. I was contacted by an oil valley petroleum about leasing the mineral rights but the representative said my dad only owned 25 acres of mineral rights. So I waited until the lease came to see which land description they wanted to lease, but on the lease it combines the two land descriptions as follows E/2 NE/4 NE/4, SE/4 NE/4, SE/4 SW/4 NE/4 Section 26, Township 4 South, Range 2 East. We contacted the county clerk a week ago to try to get clarification but have not heard anything back. I am just trying to figure out if he owns 25 or 50 acres of rights, I am not familiar with land descriptions.

The way I read it there is 25 net mineral acres total.

Section 26 Township 4 South Range 2 East is 1 square mile = 640 acres.

S/2 SE/4 NE/4 is read right to left. The first 1/4 description reduces it to 160 acres, a 1/4 of that would be 40 and so on. NE/4 is 160, SE/4 would be 40 and S/2 would make it = 20.

SE/4 SW/4 NE/4 would be 10. 160, 20 = 10.

E/2 NE/4 NE/4 = 20.

N/2 SE/4 NE/4 = 20.

70 acres, 25/70 makes it 25 acres.

The description they provided also is 70 acres and appears to cover the same area.

E/2 NE/4 NE/4 = 20.

SE/4 NE/4 = 40.

SE/4 SW/4 NE/4 = 10.

Thank you SO much for such a prompt, detailed, informative answer! I have spent so many hours online trying to figure this out, I wish I posted this here first!