Doc, The lucite handled Buck knives were made from 1945-54 (even 55). These were the HH and Al Buck knives. Afterward, this handle material and using files as raw materials gave way to hardwood handles and antler. From 1955-60. Afterward a different era began in 61 & 62 which is that of 440C blades and phenolic handles. Procure a copy of 'Blades's Guide To Knives', edited by Steve Shackleford to continue your readings on this subject. DM