Sarah's Necklace

She had always wondered why Jareth never took off the strange necklace that hung in his open shirt. And when she received this, she knew it was not a mere gift or trinket. It vaguely resembles a smaller version of his necklace outlined with green pearly shillings that is almost the same color as her green eyes. Why would he give her something so exquisite and constantly reminding her of the Goblin King?