William Henry’s new collection of cuff links are relics for the wrist. The 10 debut styles (priced from $250 to $550) have been fashioned from rare materials like the fossilized tooth of a wooly mammoth unearthed from the North Sea, which the designer cross-sectioned and set in platinum ($500). The cuff link’s design reveals the tooth’s delicate interior—layers of alternating quartz-like striations, which were air-dried for one year before being resin-stabilized and set. Other styles include fossilized coral a…