Genesis 25:6 (KJV)

Then again Abraham took a wife, and her name was Keturah.

And she bare him Zimran, and Jokshan, and Medan, and Midian, and Ishbak, and Shuah.

And Jokshan begat Sheba, and Dedan. And the sons of Dedan were Asshurim, and Letushim, and Leummim.

And the sons of Midian; Ephah, and Epher, and Hanoch, and Abidah, and Eldaah. All these were the children of Keturah.

And Abraham gave all that he had unto Isaac.

And these are the days of the years of Abraham's life which he lived, an hundred threescore and fifteen years.

Then Abraham gave up the ghost, and died in a good old age, an old man, and full of years; and was gathered to his people.

And his sons Isaac and Ishmael buried him in the cave of Machpelah, in the field of Ephron the son of Zohar the Hittite, which is before Mamre;

The field which Abraham purchased of the sons of Heth: there was Abraham buried, and Sarah his wife.

And it came to pass after the death of Abraham, that God blessed his son Isaac; and Isaac dwelt by the well Lahairoi.