'Signet' in the Bible

And he said, What pledge shall I give thee? And she said, Thy signet and thy cord, and thy staff that is in thy hand. And he gave them to her, and came in unto her, and she conceived by him.

When she was brought forth, she sent to her father-in-law, saying, By the man, whose these are, am I with child: and she said, Discern, I pray thee, whose are these, the signet, and the cords, and the staff.

And Pharaoh took off his signet ring from his hand, and put it upon Joseph's hand, and arrayed him in vestures of fine linen, and put a gold chain about his neck;