Here you go Ken. Abraham's 2nd wife.https://en.wikipedia.org/wiki/Keturah
One of those hardcore Puritan-style Bible names, I suppose, that never caught on properly.
I've had no end of trouble with 'em, particularly when the parish clerk/census enumerator's handwriting was very florid, or his grasp of spelling primitive.
"Lessee now ... is that "Susannah"? Or "Laruhamah"? " (apparently in the running for a cool girls' name, back in ye olden dayes).