ZDP-189, a premium Japanese powdered super-steel made by Hitachi, hardened into the mid & upper Rc 60s (!), with very high carbide volume, superior edge retention, and the ability to maintain steep edge angles (at some cost to toughness and corrosion resistance, but “not as much of a compromise as you might expect,” say many.) Comparable to S90V. Complaints of staining (despite its high levels of chromium) and difficult sharpening. Sometimes laminated between tougher, more corrosion resistant steels such as 420J. Cost is about 20x higher than VG-10. Difficult to obtain a super edge, but holds it much longer once obtained. Has 3% carbon! (That’s a whole lot o' carbon!) In the 2008 lineup, it's found in the C90 Stretch II, special versions of the C11 Delica, C10 Endura and C65 Bob Lum Chinese Folder, and clad with 420J in the C113 Caly III CF and the discontinued C52 Calypso Jr.
Spyderco used solid ZDP-189 for the first time in a C11 Delica Sprint run in 2006.
ZDP-189 consists of: